Laser Radiation

Laser Radiation

Laser radiation is an optical radiation that can either be visible or invisible. If the wavelength of a laser beam is 400-780nm (nanometres), the beam is visible to the human eye. But when the environment air is clean from flying dust and other particles, the beam itself may not be visible, except for the mirror point on the targeted object. Invisible laser radiation is mostly infrared radiation, but UV-lasers also exist. Laser with an invisible beam is dangerous because when a person cannot see it, they cannot sense danger. In the case of an accident, when the infrared laser beam strikes the eye, a person does not sense it as light – meaning that no defence reaction (closing eyes, squinting, or iris contraction) follows, and this can result in irreversible damage to the eye retina. Therefore, work zones of laser instruments must be clearly marked and care taken that the beam would not hit bystanders.

Laser radiation is a special case of optic radiations, as the beam makes the laser dangerous also very far from its’ source; whereas some other optical or invisible light energy (from lamps, for example) disperses notably when the distance increases.

Lazer nurlanishi

Lazer nurlanishi bu ko'rinadigan yoki ko'rinmaydigan bo'lishi mumkin bo'lgan optik nurlanishdir. Agar lazer nurining to'lqin uzunligi 400-780 nm (nanometr) bo'lsa, nur inson ko'ziga ko'rinadi. Ammo atrof-muhit havosi uchib ketadigan chang va boshqa zarrachalardan toza bo'lsa, nishonning o'zi ko'zga ko'rinmasligi mumkin, maqsadli ob'ektdagi ko'zgu nuqtasi bundan mustasno. Ko'rinmas lazer nurlanishi asosan infraqizil nurlanishdir, ammo UB nurlari ham mavjud. Ko'zga ko'rinmas nurli lazer xavflidir, chunki odam uni ko'ra olmasa, ular xavfni sezmaydilar. Baxtsiz hodisa yuz berganida, infraqizil lazer nuri ko'zga tegsa, odam buni engil deb bilmaydi - bu hech qanday mudofaa reaktsiyasi (ko'zlarni yumish, qichishish yoki irisning qisqarishi) kuzatilmaydi va bu qaytarilmas zararga olib kelishi mumkin. ko'zning to'r pardasi. Shuning uchun lazer asboblarining ish zonalari aniq belgilangan bo'lishi kerak va nurlar to'siqlarga tegmasligi uchun ehtiyot bo'lish kerak. Lazer nurlanishi - optik nurlanishning alohida holati, chunki nur lazerni o'z manbasidan juda ham xavfli qiladi; boshqa optik yoki ko'rinmas yorug'lik energiyasi (masalan, chiroqlardan) masofa oshganda sezilarli darajada tarqaladi

Learn more about Laser Radiation

Abstract:

Laser radiation forces applied in fully transparent, highly entangled semi-dilute polymer solutions generate freestanding, threedimensional, micro- and, potentially, nano-solids. The underlying phenomena are attributed to a synergy of effects involving the radiation forces exerted by milliwatt laser beams on polymer chains and the entanglement of macromolecules. Most importantly, since the primary stages of formation, the incident optical field is structured and guided by the induced microstructures. This self-confinement enhances the effect and results in great compression of the material, osmotic solvent extraction and, eventually, materials solidification in free space. Structural reversibility verifies the absence of any chemical modification of the material. These innovative concepts are demonstrated through the fabrication of microstructures, including among others plasmonic and fluorescent semiconductor quantum–dot hybrid structures, as well as polymer fibers also drawn by laser radiation forces. The phenomenology of the involved effects is plausibly explained here and further research will resolve the fundamental aspects and lead the way forward to new and emerging concepts for future microfabrication technologies.

Lazer nurlanishining mavhumligi haqida ko'proq ma'lumot oling: To'liq shaffof, juda aralashgan yarim suyultirilgan polimer eritmalarida qo'llaniladigan lazer nurlanish kuchlari erkin, uch o'lchovli, mikro va potentsial nano-eritmalar hosil qiladi. Ushbu hodisalar polimer zanjirlari va makromolekulalarni bog'lab turadigan milliattli lazer nurlari orqali yuboriladigan nurlanish kuchlari ta'sirining sinergiyasiga bog'liq. Eng muhimi, shakllanishning boshlang'ich bosqichlaridan beri intsident optik maydoni induktsiyalangan mikro tuzilmalar tomonidan boshqariladi va boshqariladi. Bu o'z-o'zini ushlab turish ta'sirni kuchaytiradi va materialni katta siqishni, erituvchini ozmotik ekstraktsiyasi va natijada bo'sh joylarda materiallarning mustahkamlanishiga olib keladi. Strukturaviy o'zgaruvchanlik materialning biron bir kimyoviy modifikatsiyasi yo'qligini tasdiqlaydi. Ushbu innovatsion g'oyalar plazmonik va lyuminestsent yarimo'tkazgichli kvantli nuqta gibrid tuzilmalar, shuningdek, lazer nurlanish kuchlari yordamida chizilgan polimer tolalari mikro tuzilmalarni to'qish orqali namoyish etiladi. Bu erda ta'sirlangan ta'sirlarning fenomenologiyasi aniq tushuntiriladi va kelgusidagi tadqiqotlar fundamental tomonlarini hal qiladi va kelajakda mikrofilmlar texnologiyalari uchun yangi va paydo bo'ladigan tushunchalarga yo'l ochadi.

Lasers in dentistry

20.3 History of the application of laser radiation in dentistry

Laser radiation (wavelength 694 nm – ruby laser (see Chapter 4 for details)) was first employed in dentistry in hard tissue treatments, such as caries removal and cavity preparation, as a substitute for mechanical cutting and drilling. Since the first use of this laser on hard dental tissuein vitro by Stern and Sognnaes (Stern and Sognnaes, 1964) and in vivo by Goldman (Goldman et al., 1965; Goldman, 1967) various types of lasers have found their place in various fields of dentistry and oral medicine. Nd:YAG laser radiation was first used and reported by Yamamoto and his colleagues in 1974 (Yamamoto and Ooya, 1974). They showed that the Nd:YAG (wavelength 1064 nm) radiation can inhibit the formation of incipient caries. As seen in Fig. 1.24, the absorption of investigated laser radiation in water as well as in hydroxyapatite is minimal; therefore, when the tooth is exposed to this radiation, the part of it passing through enamel and dentin heats the root and can damage it. Therefore ruby laser radiation, and later on also the Nd:YAG laser, was not recommended for hard tissue dentistr

Stomatologiyada lazerlar

20.3 Stomatologiyada lazer nurlanishini qo'llash tarixi

Lazer nurlanishi (to'lqin uzunligi 694 nm - yoqut lazer (batafsil ma'lumot uchun 4-bobga qarang)) birinchi marta stomatologiyada kariesni olib tashlash va bo'shliqlarni tayyorlash kabi qattiq to'qimalarni davolashda ishlatilgan. mexanik chiqib ketish va burg'ulash uchun o'rinbosar. Ushbu lazerni Stern va Sognnaes (Stern and Sognnaes, 1964) tomonidan vivo jonli ravishda tish to'qimalarining vitroiga birinchi marta qo'llaganidan beri (Goldman va boshqalar, 1965; Goldman, 1967) turli xil lazerlar turli xil turlarda o'z o'rnini topdi. stomatologiya va og'zaki tibbiyot yo'nalishlari. Nd: YAG lazer nurlanishi birinchi marta Yamamoto va uning hamkasblari tomonidan 1974 yilda ishlatilgan va xabar qilingan (Yamamoto va Ooya, 1974). Ular Nd: YAG (to'lqin uzunligi 1064 nm) radiatsiya kiruvchi kariesning shakllanishiga to'sqinlik qilishi mumkinligini ko'rsatdi. 1.24-rasmdan ko'rinib turibdiki, tadqiq qilingan lazer nurlanishining suvda va gidroksiapatitda singishi minimaldir; shu sababli, tish bu nurlanishga duchor bo'lganida, uning emaye va dentin orqali o'tadigan qismi ildizni isitadi va unga zarar etkazishi mumkin.

Laser

The applications of laser in industry and science are so many and so varied as lo susjcst magic. Scientists in many countries working at a very inieresting problem: combining the two big technological discoveries of the second half of the 20th centry -laser and thermonuclear reaction — to produce a practically limitless source of energy. Physicists of this country have developed large laser installations to conduct physical experiments in heating thermonuclear fuel wiih laser beams. There also exists an idea to use laser for solving the problem of controlled thermonuclear reaction. The laser beam must heat ihe fuel to the required temperature so quickly that the plasma does not have time to disintegrate. According to current estimates, the duration of the pulse has to be approximately a billionth of a second. The light capacity of this pulse would be dozens of times greater than the capacity of all the world's power plants. To meet such demands in practice, scientists and enginners must work hard as it is clear that a lot of difficulties are to be encountered on route.

The laser's most important potential may be its use in communications. The intensity of a laser can be rapidly changed to encode very complex signals. In principle, one laser beam, vibrating a billion times faster than ordinary radio waves, could carry the radio,TV and telephone messages of the world simultaneously. In just a fraction of a second, for example, one laser beam could transmit the entire texl of the Encyclopaedia Britannica.

Besides, there are projects to use lasers for long distance communication and for transmission of energy to space stations, to the surface of the Moon or to planets in the Solar system. Projects have also been suggested to place lasers aboard Earth satellites nearer to the Sun in order to transform the solar radiation into laser beams, with this transformed energy subsequently trasmitted lo the Earth or to other space bodies. These projects have nol yet been put into effect, because of the great technological difficulties to be overcome and, therefore, the great cost involved. But there is no doubt that in time these projects will be realized and the laser beam will begin operating in outer space as well.

Lazer

Lazerning sanoat va ilm-fan sohalarida qo'llanilishi juda ko'p va juda ko'p turli xil bo'lib, ular lo sejcst sehriga o'xshaydi. Ko'pgina davlatlarning olimlari juda katta muammoga duch kelmoqdalar: 20-asrning ikkinchi yarmidagi ikkita katta texnologik kashfiyotlar - termoyadroviy reaktsiya va cheksiz energiya manbai ishlab chiqarish. Ushbu mamlakat fiziklari termoyadro yoqilg'isi va lazer nurlarini isitish bo'yicha fizik tajribalarni o'tkazish uchun katta lazer qurilmalarini ishlab chiqdilar. Shuningdek, boshqariladigan termoyadroviy reaktsiya muammosini hal qilish uchun lazerdan foydalanish g'oyasi mavjud. Lazer nurlari yoqilg'ini kerakli haroratga qadar tezroq qizdirishi kerak, shunda plazmaning parchalanishiga vaqt qolmaydi. Amaldagi hisob-kitoblarga ko'ra, pulsning davomiyligi sekundning milliarddan biriga teng bo'lishi kerak. Ushbu pulsning yorug'lik sig'imi dunyodagi barcha elektr stantsiyalarining quvvatidan o'nlab baravar katta bo'ladi. Amalda bunday talablarni qondirish uchun olimlar va ishbilarmonlar astoydil harakat qilishlari kerak, chunki yo'lda ko'plab qiyinchiliklarga duch kelish kerakligi aniq. Lazerning eng muhim potentsiali aloqa vositalarida foydalanish bo'lishi mumkin. Juda murakkab signallarni kodlash uchun lazerning intensivligini tezda o'zgartirish mumkin. Aslida, oddiy radio to'lqinlaridan milliard marta tez tebranadigan bitta lazer nurlari dunyoning radio, televidenie va telefon xabarlarini bir vaqtning o'zida olib yurishi mumkin edi. Masalan, soniyalarning bir qismigina, masalan, bitta lazer nurlari Britannica Encyclopedia nashrining butun matnini uzatishi mumkin edi. Bundan tashqari, uzoq masofali aloqa va energiyani kosmik stantsiyalarga, Oy yuzasiga yoki Quyosh tizimidagi sayyoralarga uzatish uchun lazerlardan foydalanish bo'yicha loyihalar mavjud. Lazerlarni Quyoshga yaqin bo'lgan Yerning sun'iy yo'ldoshlari orasiga lazer nurlarini lazer nurlariga aylantirish uchun joylashtirish taklif qilinmoqda, keyinchalik bu o'zgartirilgan energiya Yerga yoki boshqa kosmik jismlarga tegdi. Ushbu loyihalar hali ham kuchga kirdi, chunki ularni echishda katta texnologik qiyinchiliklar va shuning uchun katta xarajatlar talab etiladi. Vaqt o'tishi bilan ushbu loyihalar amalga oshishiga va lazer nurlari tashqi kosmosda ham ishlay boshlaydi.

Laser Light

Laser light is very different from normal light. Laser light has the following properties:

The light released is monochromatic. It contains one specific wavelength of light (one specific color). The wavelength of light is determined by the amount of energy released when the electron drops to a lower orbit.

The light released is coherent. It is “organized” -- each photon moves in step with the others. This means that all of the photons have wave fronts that launch in unison.

The light is very directional. A laser light has a very tight beam and is very strong and concentrated. A flashlight, on the other hand, releases light in many directions, and the light is very weak and diffuse.

To make these three properties occur takes something called stimulated emission. This does not occur in your ordinary flashlight -- in a flashlight, all of the atoms release their photons randomly. In stimulated emission, photon emission is organized.

Lazer nuri

Lazer nuri oddiy yorug'likdan juda farq qiladi. Lazer nuri quyidagi xususiyatlarga ega: Yorug'lik monoxromatik. U bitta yorug'likning to'lqin uzunligini (bitta o'ziga xos rang) o'z ichiga oladi. Yorug'lik to'lqin uzunligi elektron pastki orbitaga tushganda chiqariladigan energiya miqdori bilan belgilanadi. Olingan yorug'lik mos keladi. Bu "tartibga solingan" - har bir foton boshqalar bilan bir qatorda harakat qiladi. Bu shuni anglatadiki, barcha fotonlar bir xilda harakatlanadigan to'lqinli frontlarga ega. Yorug'lik juda yo'naltirilgan. Lazer nuri juda qattiq nurga ega va juda kuchli va konsentrlangan. O'z navbatida, chiroq ko'plab yo'nalishlarda yorug'lik chiqaradi va yorug'lik juda zaif va tarqoq. Ushbu uchta xususiyatning paydo bo'lishi uchun stimulyatsiya qilingan emissiya kerak bo'ladi. Bu sizning oddiy chiroqingizda sodir bo'lmaydi - chiroqda barcha atomlar o'zlarining fotonlarini tasodifiy ravishda chiqaradilar. Rag'batlantirilgan emissiyada foton emissiyasi tashkil etiladi.

How a Laser Works

Basic Principle

A laser oscillator usually comprises an optical resonator (laser resonator, laser cavity) in which light can circulate (e.g. between two mirrors), and within this resonator a gain medium (e.g. a laser crystal), which serves to amplify the light. Without the gain medium, the circulating light would become weaker and weaker in each resonator round trip, because it experiences some losses, e.g. upon reflection at mirrors. However, the gain medium can amplify the circulating light, thus compensating the losses if the gain is high enough. The gain medium requires some external supply of energy – it needs to be “pumped”, e.g. by injecting light (optical pumping) or an electric current (electrical pumping → semiconductor lasers). The principle of laser amplification is stimulated emission.

Lazer qanday ishlashini asosiy printsipi

Lazer osilator odatda optik rezonatorni (lazer rezonatori, lazer bo'shlig'i) o'z ichiga oladi, unda yorug'lik aylana oladi (masalan, ikkita nometall) va shu rezonator ichida xizmat qiluvchi vosita (masalan, lazer kristalli). yorug'likni kuchaytiring. Yutish vositasi bo'lmaganda, aylanuvchi yorug'lik har bir rezonatorning har safar safari davomida kuchsizroq va zaifroq bo'ladi, chunki u ba'zi yo'qotishlarni boshdan kechiradi, masalan. nometall aks etganda. Biroq, daromad ortishi aylanayotgan yorug'likni kuchaytirishi mumkin, va agar daromad etarli darajada yuqori bo'lsa, yo'qotishlarni qoplaydi. Daromad ortig'i tashqi energiya ta'minotini talab qiladi - uni "pompalash" kerak, masalan. yorug'lik (optik nasos) yoki elektr tokini (elektr nasos → yarimo'tkazgichli lazerlar) kiritish orqali. Lazerni kuchaytirish printsipi stimulyatsiya qilingan emissiya hisoblanadi.

Types of Semiconductor Lasers

There is a great variety of different semiconductor lasers, spanning wide parameter regions and many different application areas:

Small edge-emitting laser diodes generate a few milliwatts (or up to 0.5 W) of output power in a beam with high beam quality. They are used e.g. in laser pointers, in CD players, and for optical fiber communications.

External cavity diode lasers contain a laser diode as the gain medium of a longer laser cavity. They are often wavelength-tunable and exhibit a small emission linewidth.

Both monolithic and external-cavity low-power levels can also be mode-locked for ultrashort pulse generation.

Broad area laser diodes generate up to a few watts of output power, but with significantly poorer beam quality.

High-power diode bars contain an array of broad-area emitters, generating tens of watts with poor beam quality.

High-power stacked diode bars contain stacks of diode bars for the generation of extremely high powers of hundreds or thousands of watts.

Surface-emitting lasers (VCSELs) emit the laser radiation in a direction perpendicular to the wafer, delivering a few milliwatts with high beam quality.

Optically pumped surface-emitting external-cavity semiconductor lasers (VECSELs) are capable of generating multi-watt output powers with excellent beam quality, even in mode-locked operation.

Quantum cascade lasers operate on intraband transitions (rather than interband transitions) and usually emit in the mid-infrared region, sometimes in the terahertz region. They are used e.g. for trace gas analysis.

Yarimo'tkazgichlarning lazer turlari

Turli xil yarim Supero'tkazuvchilar lazerlar juda ko'p, ular keng parametrli mintaqalarni va turli xil dastur sohalarini o'z ichiga oladi: Kichik chekka lazerli diodlar yuqori nurli nurda bir necha milliatt (yoki 0,5 Vt gacha) chiqish kuchini hosil qiladi. sifati. Ular ishlatiladi lazer markerlarida, CD pleerlarda va optik tolali aloqa uchun. Tashqi kavitali diodli lazerlar lazer diyotini o'z ichiga oladi, chunki bu lazerli bo'shliqning uzunligini oshiradi. Ular ko'pincha to'lqin uzunligi bo'yicha sozlanadi va kichik emissiya liniyasini namoyish etadi. Ikkala monolit va tashqi bo'shliqning kam quvvat darajasi ham ultrashort pulslarini ishlab chiqarish uchun rejim bilan bloklanishi mumkin. Keng maydonli lazerli diodlar bir necha vattgacha chiqish quvvatini ishlab chiqaradi, ammo nur sifati ancha past. Yuqori quvvatli diodli barlarda nurlanish sifati past bo'lgan o'nlab vattlarni chiqaradigan keng doiradagi emitentlar mavjud. Yuqori quvvatli diodli barlarda yuzlab yoki minglab vattlarning o'ta yuqori kuchlarini ishlab chiqarish uchun diodli novlar mavjud. Yuzaga chiqadigan lazerlar (VCSELS) lazer nurlanishini gofretga perpendikulyar yo'nalishda chiqaradi va yuqori sifatli nurga ega bo'lgan bir necha milliattni beradi. Optik pompalanadigan sirt chiqaradigan tashqi bo'shliqli yarimo'tkazgich lazerlari (VECSELS), hatto o'chirilgan rejimda ham juda yaxshi nur sifati bilan ko'p vattli chiqish quvvatini yaratishga qodir. Kvant kaskadli lazerlar tarmoq ichidagi o'tishlarni (interbandli o'tishlardan ko'ra) ishlaydi va odatda o'rta infraqizil mintaqada, ba'zan teraxerts mintaqasida chiqariladi. Ular ishlatiladi iz gazini tahlil qilish uchun.

LASER

LASER Introduction

Before going into how LASER (Light Amplification by Stimulated Emission of Radiation) works, let’s first take a look at how light works.

What is Light?

Light is a kind of energy released by an atom. Light is made up of very small particles called photons.

Atoms are the basic units of matter. Each atom consists of a nucleus and a set of electrons orbiting the nucleus.

Nucleus is formed as a result of strong nuclear force between the protons and neutrons. Protons have positive charge so they are referred as positively charged particles. Neutrons do not have charge so they are referred as neutral particles.

Neutrons do not have charge so the overall charge of the nucleus is positive.

Atoms are the basic units of matter. Each atom consists of a nucleus and a set of electrons orbiting the nucleus.

Electrons have negative charge so they are referred as negatively charged particles. Electrons always orbit the nucleus because of the electrostatic force of attraction present between them. Electrons revolve around the nucleus in different orbits or shells. Each orbit has a unique energy level.

The electrons orbiting at a larger distance from the nucleus have higher energy level whereas the electrons orbiting at a smaller distance from the nucleus have lower energy level.

The electrons in the lower energy level need some extra energy to jump from lower energy level to the higher energy level. This extra energy can be supplied from various types of energy sources such as heat, electric field or light.

LAZER

LAZER Kirish

LAZER (Radiatsiyani stimulyatsiya qilish orqali yorug'likni kuchaytirish) qanday ishlashiga kirishdan oldin, avval yorug'lik qanday ishlashini ko'rib chiqamiz.

Yorug'lik nima?

Yorug'lik bir atom tomonidan chiqarilgan energiya turidir. Yorug'lik fotonlar deb ataladigan juda kichik zarralardan iborat. Atomlar moddaning asosiy qismidir. Har bir atom yadrodan va yadroni aylanib yuradigan elektronlar to'plamidan iborat. Yadro protonlar va neytronlar orasidagi kuchli yadro kuchi natijasida hosil bo'ladi. Protonlar musbat zaryadga ega, shuning uchun ular musbat zaryadlangan zarralar deb nomlanadi. Neytronlar zaryadga ega emaslar, shuning uchun ular neytral zarrachalar deb ataladi. Neytronlarda zaryad bo'lmaydi, shuning uchun yadroning umumiy zaryadi ijobiy bo'ladi. Atomlar moddaning asosiy qismidir. Har bir atom yadrodan va yadroni aylanib yuradigan elektronlar to'plamidan iborat. Elektronlar manfiy zaryadga ega, shuning uchun ular manfiy zaryadlangan zarralar deb ataladi. Elektronlar har doim ular orasidagi elektrostatik tortishish kuchi tufayli yadroni aylantiradilar. Elektron yadro atrofida turli orbitalarda yoki qobiqlarda aylanadi. Har bir orbitada noyob energiya darajasi mavjud. Yadrodan kattaroq masofada orbitada yurgan elektronlar yuqori energiya darajasiga ega, yadrodan kichikroq masofada orbitada turgan elektronlar esa energiya darajasiga ega. Energiya quyi darajadagi elektronlar past energiya darajasidan yuqori energiya darajasiga o'tish uchun bir oz ko'proq energiya talab qiladi. Ushbu qo'shimcha energiya issiqlik, elektr maydoni yoki yorug'lik kabi energiya manbalaridan olinishi mumkin.

Organic Laser Diodes Move From Dream to Reality

An organic laser diode emitting blue laser light, as reported by researchers at Kyushu University’s Center for Organic Photonics and Electronics Research. Credit: Atula S. D. Sandanayaka

Researchers from Japan have demonstrated that a long-elusive kind of laser diode based on organic semiconductors is indeed possible, paving the way for the further expansion of lasers in applications such as biosensing, displays, healthcare, and optical communications.

Long considered a holy grail in the area of light-emitting devices, organic laser diodes use carbon-based organic materials to emit light instead of the inorganic semiconductors, such as gallium arsenide and gallium nitride, used in traditional devices.

The lasers are in many ways similar to organic light-emitting diodes (OLEDs), in which a thin layer of organic molecules emits light when electricity is applied. OLEDs have become a popular choice for smartphone displays because of their high efficiency and vibrant colors, which can easily be changed by designing new organic molecules.

Organic laser diodes produce a much purer light enabling additional applications, but they require currents that are magnitudes higher than those used in OLEDs to achieve the lasing process. These extreme conditions caused previously studied devices to break down well before lasing could be observed.

Further complicating progress, previous claims of electrically generated lasing from organic materials turned out to be false on several occasions, with other phenomena being mistaken for lasing because of insufficient characterization.

But now, scientists from the Center for Organic Photonics and Electronics Research (OPERA) at Kyushu University report in the journal Applied Physics Express that they have enough data to convincingly show that organic semiconductor laser diodes have finally been realized.

“I think that many people in the community were doubting whether we would actually one day see the realization of an organic laser diode,” says Atula S. D. Sandanayaka, lead author on the paper, “but by slowing chipping away at the various performance limitations with improved materials and new device structures, we finally did it.”

Organik lazerli diodlar orzudan haqiqatga o'tmoqda

Kyushu universitetining Organik fotonika va elektron tadqiqotlar markazining tadqiqotchilari xabar berishicha, ko'k lazer nurini chiqaradigan organik lazer diodi. Kredit: Atula S. Sandanayaka

Yaponiya tadqiqotchilari, organik yarimo'tkazgichlarga asoslangan lazer diyotining uzoq vaqt turishi haqiqatan ham mumkinligini isbotladilar, bu biosensing, displeylar, sog'liqni saqlash va optik aloqa kabi sohalarda lazerlarni yanada kengaytirishga yo'l ochib berdi. Uzoq vaqtdan beri yorug'lik chiqaradigan qurilmalar muqaddas panjara hisoblanadi, organik lazerli diodlar an'anaviy qurilmalarda ishlatiladigan galiy arsenid va galliy nitridi kabi noorganik yarimo'tkazgichlar o'rniga yorug'lik chiqarishda uglerod asosidagi organik materiallardan foydalanadi. Lazerlar ko'p jihatdan organik yorug'lik chiqaradigan diodlarga (OLEDS) o'xshaydi, bunda elektr energiyasi qo'llanilganda organik molekulalarning yupqa qatlami yorug'lik chiqaradi. OLEDS yuqori samaradorligi va jonli ranglari tufayli smartfonlar displeylari uchun mashhur tanlovga aylandi, ularni yangi organik molekulalarni loyihalash orqali osongina o'zgartirish mumkin. Organik lazer diyotlari qo'shimcha dasturlarni ishlatishga imkon beradigan yanada toza yorug'likni chiqaradi, ammo lizing jarayoniga erishish uchun ular OLEDS-da ishlatilganidan kattaroq bo'lgan toklarni talab qiladi. Ushbu ekstremal sharoitlar, oldin o'rganilgan qurilmalarni lizingga olishdan oldin yaxshi buzilishiga olib keldi. Ilgarilab borishni yanada murakkablashtirgan holda, organik materiallardan elektr energiyasini ishlab chiqaradigan lizingga oid da'volar bir necha bor yolg'on bo'lib chiqdi, boshqa hodisalar xarakteristikaning etarli emasligi sababli lizingga berildi. Ammo hozir, Kyushu universitetidagi Organik fotonika va elektron tadqiqotlar markazi (OPERA) olimlari "Amaliy fizika ekspress" jurnalida hisobotida organik yarimo'tkazgichli lazer diodlari nihoyat amalga oshirilganligini isbotlash uchun etarli ma'lumotlarga ega ekanliklarini aytishdi. "Menimcha, ko'pchilik odamlar biz bir kun organik lazer diodi to'g'risida haqiqatan ham ko'rishimiz mumkinmi degan savolga shubha qilishdi", deydi qog'ozdagi qo'rg'oshin muallifi Atula SD Sandanayaka, - ammo turli xil ishlash cheklovlarini sekinlashtirish bilan. takomillashtirilgan materiallar va yangi qurilmalar tuzilmalari, biz nihoyat buni qildik. "

Proton Beam Energy Doubled with Colliding Lasers

How a proton beam can double its energy. ​A standard laser generated proton beam is created through firing a laser pulse at a thin metallic foil. The new method involves instead first splitting the laser into two less intense pulses, before firing both at the foil from two different angles simultaneously. When the two pulses collide on the foil, the resultant electromagnetic fields heat the foil extremely efficiently. The technique results in higher energy protons whilst using the same initial laser energy as the standard method.​ Image: Yen Strandqvist

Researchers from Sweden’s Chalmers University of Technology and the University of Gothenburg present a new method, which can double the energy of a proton beam produced by laser-based particle accelerators. The breakthrough could lead to more compact, cheaper equipment that could be useful for many applications, including proton therapy.​​​

Proton therapy involves firing a beam of accelerated protons at cancerous tumors, killing them through irradiation. But the equipment needed is so large and expensive that it only exists in a few locations worldwide. ​

Modern high-powered lasers offer the potential to reduce the equipment’s size and cost, since they can accelerate particles over a much shorter distance than traditional accelerators—reducing the distance required from kilometers to meters. The problem is, despite efforts from researchers around the world, laser generated proton beams are currently not energetic enough. But now, the Swedish researchers present a new method which yields a doubling of the energy—a major leap forward.

The standard approach involves firing a laser pulse at a thin metallic foil, with the interaction resulting in a beam of highly charged protons. The new method involves instead first splitting the laser into two less intense pulses, before firing both at the foil from two different angles simultaneously. When the two pulses collide on the foil, the resultant electromagnetic fields heat the foil extremely efficiently. The technique results in higher energy protons whilst using the same initial laser energy as the standard approach.

“This has worked even better than we dared hope. The aim is to reach the energy levels that are actually used in proton therapy today. In the future it might then be possible to build more compact equipment, just a tenth of the current size, so that a normal hospital could be able to offer their patients proton therapy,” says Julien Ferri, a researcher at the Department of Physics at Chalmers, and one of the scientists behind the discovery.

Lazerlarning to'qnashuvi bilan proton nurining energiyasi ikki baravar ko'paydi

Normal lazer yordamida yaratilgan proton Proton nurlari energiyasini qanday oshirishi mumkin. nur lazer pulsini ingichka metall folga ustiga otish orqali yaratiladi. Yangi usul birinchi navbatda lazerni ikkita zich impulslarga bo'lishdan iborat, bunda folga ikkala burchakdan bir vaqtning o'zida ikkala yoqishdan oldin. Ikki puls folga ustiga to'qnashganda, elektromagnit maydon folga juda samarali isitadi. Texnika standart energiya bilan bir xil boshlang'ich lazer energiyasidan foydalanganda ko'proq energiya protoniga olib keladi. Rasm: Yen Strandqvist Shvetsiyaning Chalmers texnologiya universiteti va Gothenburg universiteti tadqiqotchilari lazer asosidagi zarracha tezlatgichlari tomonidan ishlab chiqarilgan proton nurining energiyasini ikki baravar oshiradigan yangi usulni taqdim etishdi. Ushbu yutuq ko'plab ixcham va arzon uskunalarga olib kelishi mumkin, ular ko'plab dasturlar, shu jumladan proton terapiyasi uchun foydali bo'lishi mumkin. Proton terapiyasi saraton o'smalarida tezlashtirilgan protonlar nurini tarqatishni va nurlantirish orqali o'ldirishni o'z ichiga oladi. Ammo zarur bo'lgan uskunalar juda katta va qimmat bo'lgani uchun, u faqat dunyoning bir necha joylarida mavjud. Zamonaviy yuqori quvvatli lazerlar uskunaning hajmi va narxini pasaytirish uchun potentsialni taklif qiladi, chunki ular zarrachalarni an'anaviy tezlatgichlarga qaraganda ancha qisqa masofada tezlashtirishi mumkin - bu kilometrdan metrgacha talab qilinadigan masofani kamaytiradi. Muammo shundaki, butun dunyo tadqiqotchilarining sa'y-harakatlariga qaramay, lazerli proton nurlari hozircha etarlicha baquvvat emas. Ammo hozirda shved tadqiqotchilari oldinga katta sakrash evaziga energiyani ikki baravar ko'paytirishga imkon beradigan yangi usulni taqdim etishmoqda. Standart yondoshuv ingichka metall folga ichida lazer nayzasini otishni o'z ichiga oladi, shu bilan o'zaro ta'sirda yuqori zaryadlangan proton nurlari paydo bo'ladi. Yangi usul birinchi navbatda lazerni ikkita zich impulslarga bo'lishdan iborat, bunda folga ikkala burchakdan bir vaqtning o'zida ikkala yoqishdan oldin. Ikki puls folga ustiga to'qnashganda, elektromagnit maydon folga juda samarali isitadi. Texnika standart energiya bilan bir xil boshlang'ich lazer energiyasidan foydalanganda ko'proq energiya protoniga olib keladi. "Bu biz umid qilganimizdan ham yaxshiroq ishladi. Maqsad bugungi kunda proton terapiyasida ishlatiladigan energiya sathiga erishishdir. Kelajakda hozirgi hajmning o'ndan bir qismini tashkil qiladigan yanada ixcham uskunalar ishlab chiqarish mumkin. shunda oddiy kasalxona o'z bemorlariga proton terapiyasini taklif qilishi mumkin ", - deydi Chalmers fizikasi kafedrasi ilmiy xodimi va kashfiyotning asoschilaridan biri Julien Ferri.

Specific Challenge:

Directed energy systems, and in particular laser systems, are potential game changers in future military activities[1]. They are capable to engage rapidly and precisely with agile targets at a low operational cost per shot and with a reduced risk to certain types of collateral damage. This makes them particularly attractive to counter a variety of threats, ranging from asymmetric threats such as incoming, low cost unmanned vehicles to Rocket, Artillery, Mortar (RAM) or missiles which conventionally would require expensive countermeasures such as guided missiles. Laser systems also face a number of limitations, in particular their sensitivity to absorption and scattering which lead to decreased beam quality under adverse atmospheric conditions and hence reduce the circumstances in which the system can effectively be used.

In essence, the thermal interaction between the laser beam and the target ultimately leads to irreversible damage if the temperature of the target material can be raised sufficiently high. Therefore the laser output power should be as high as possible while maintaining a high beam quality to focus and lock the laser beam to a small spot size on the target. This allows reaching sufficiently high power densities to reduce the exposure time needed to induce critical failure of the target material.

Different designs based on different laser technologies have been developed to deliver output powers ranging from the kW-level up to several MW. The lower power levels are sufficient to affect soft, unmanned aerial vehicles (UAV) at short ranges (several hundreds of meters up to the kilometre range) while airborne MW-laser systems demonstrated to be able to counter ballistic missiles from a distance of hundreds of kilometres.

Current research and development (R&D) efforts aim to develop laser systems that combine several or many high output powers with a compact design to enable integration in mobile platforms, such as ships, trucks or helicopters. The required laser output power is directly linked to the target(s) and their associated scenario(s), the laser system architecture and performance. As a first estimate, high quality laser beams with output powers higher than 100 kW would enable to address the full target spectrum from tactical unmanned aerial vehicles (UAVs) up to certain types of missiles. Non-European countries have already demonstrated compact laser effectors generating up to 100 kW, and roadmaps are proposed to scale the powers well above the 100 kW level in the coming years. Over the last decade, the increase in the laser effector power in non-European countries relies merely on studies of new architectures, including incoherent, coherent and spectral beam combining.

Maxsus qiyinchilik:

Yo'naltirilgan energiya tizimlari va xususan lazer tizimlari kelajakdagi harbiy harakatlardagi potentsial o'yinlarni o'zgartiruvchidir [1]. Ular tez va aniq zarbalar bilan zarba berishning kam xarajati bilan va garovga qo'yilgan zararning ayrim turlarini kamaytirgan holda tezkor va aniq zarbalarni amalga oshirishga qodir. Bu ularni turli xil tahdidlarga qarshi turishga jalb qiladi, masalan, kirish, arzon narxlardagi uchuvchisiz transport vositalari, Raketa, Artilleriya, Mortar (RAM) yoki boshqariladigan raketalar kabi qimmat qarshi choralarni talab qiladigan raketalar. Lazer tizimlari, shuningdek, bir qator cheklovlarga duch kelmoqdalar, xususan, ularning yutilish va tarqalishga sezgirligi noqulay atmosfera sharoitida nur sifatini pasayishiga olib keladi va shu sababli tizimdan samarali foydalanish mumkin bo'lgan vaziyatlarni kamaytiradi. Aslida, lazer nuri va nishon o'rtasidagi termal o'zaro ta'sir, agar maqsad qilingan materialning harorati etarlicha ko'tarilishi mumkin bo'lsa, qaytarib bo'lmaydigan zararga olib keladi. Shuning uchun lazerning chiqish kuchi iloji boricha yuqori bo'lishi kerak va lazer nurini nishonning kichik joyiga tutash va qulflash uchun yuqori nur sifatini saqlab turishi kerak. Bu maqsadga muvofiq materialning tanqidiy ishdan chiqishiga olib keladigan ta'sir qilish vaqtini kamaytirish uchun etarlicha yuqori quvvat zichligiga erishishga imkon beradi. KVt darajasidan bir necha MVtgacha bo'lgan quvvatlarni etkazib berish uchun turli xil lazer texnologiyalariga asoslangan turli xil dizaynlar ishlab chiqilgan. Quvvatning past darajasi yumshoq, uchuvchisiz havo vositalariga (UAV) qisqa masofalarda (bir necha yuzlab metr masofagacha) ta'sir qilish uchun kifoya qiladi, havodagi MW-lazer tizimlari esa yuzlab masofadan ballistik raketalarga qarshi tura olishlarini namoyish etishdi. km. Hozirgi izlanish va tadqiqotlar (ITI) sa'y-harakatlari kemalar, yuk mashinalari yoki vertolyotlar kabi mobil platformalarda integratsiyani amalga oshirish uchun ixcham dizayni bilan bir necha yoki ko'p yuqori chiqish kuchlarini birlashtirgan lazer tizimlarini yaratishga qaratilgan. Kerakli lazer chiqish quvvati maqsad (lar) va ular bilan bog'liq stsenariy (lar), lazer tizimining arxitekturasi va ishlashi bilan bevosita bog'liq. Dastlabki hisob-kitoblarga ko'ra, chiqish quvvati 100 kVt dan yuqori bo'lgan yuqori sifatli lazer nurlari taktik uchuvchisiz samolyotlar (UAVS) dan ma'lum turdagi raketalarga qadar to'liq maqsadli spektrni echishga imkon beradi. Evropadan tashqari mamlakatlar 100 kVtgacha ishlab chiqaradigan ixcham lazer effektorlarini namoyish etishdi va kelgusi yillarda quvvat xaritalari 100 kVt darajadan yuqori quvvatlarni kengaytirish taklif qilinmoqda. So'nggi o'n yil ichida Evropa mamlakatlarida lazer effektlari kuchayishi faqat yangi arxitekturalarni o'rganishga, shu jumladan mos kelmaydigan, izchil va spektral nurlarni birlashtirishga asoslanadi.

Second laser boosts Aeolus power

ESA’s Aeolus satellite, which carries the world’s first space Doppler wind lidar, has been delivering high-quality global measurements of Earth’s wind since it was launched almost a year ago. However, part of the instrument, the laser transmitter, has been slowly losing energy. As a result, ESA decided to switch over to the instrument’s second laser – and the mission is now back on top form.

Developing novel space technology is always a challenge, and despite the multitude of tests that are done in the development and build phases, engineers can never be absolutely certain that it will work in the environment of space.

Aeolus is, without doubt, a pioneering satellite mission – it carries the first instrument of its kind and uses a completely new approach to measuring wind from space.

The instrument, called Aladin, not only comprises the laser transmitters, but also one of the largest telescopes ESA has put into orbit and very sensitive receivers that measure the minute shifts in wavelength of light generated by the movement of molecules and particles in the atmosphere caused by the wind.

Lidar concept

Lidar concept

Aladin, works by emitting short, powerful pulses of ultraviolet light from a laser and measures the Doppler shift from the very small amount of light that is scattered back to the instrument from these molecules and particles to deliver vertical profiles that show the speed of the world’s winds in the lowermost 30 km of the atmosphere.

While scientists and meteorology centres have been thrilled with the data produced by Aeolus, the first laser’s energy was becoming a concern – and in June, energy levels dipped to the point that the quality of the wind data was set to be compromised.

Tommaso Parrinello, ESA’s Aeolus mission manager, said, “With the power from the first laser declining, we decided to turn it off and activate the second laser, which the instrument was equipped with to ensure we could address an issue such as this.

“Switching to the second laser appears to have done the trick so we’re back in business. And, we are confident that the instrument will remain in good shape for years to come.”

Ikkinchi lazer Aeolus kuchini oshiradi

ESA Aeolus sun'iy yo'ldoshi, dunyodagi birinchi kosmik Doppler shamol qopqog'ini olib yuradi, deyarli bir yil oldin ishga tushirilganidan beri, Er shamolining yuqori sifatli o'lchovlarini o'tkazmoqda. Biroq, asbobning bir qismi, lazer uzatuvchisi asta-sekin energiya yo'qotmoqda. Natijada, ESA asbobning ikkinchi lazeriga o'tishga qaror qildi - va vazifa endi eng yaxshi shaklga qaytmoqda. Kosmik yangi texnologiyalarni ishlab chiqish har doim qiyin vazifa hisoblanadi va fazalarni ishlab chiqish va qurish bosqichida o'tkazilgan ko'plab sinovlarga qaramay, muhandislar kosmik muhitda ishlashiga hech qachon amin bo'lolmaydilar. Aeolus, shubhasiz, kashshof yo'ldosh vazifasini bajaradi - u o'zining birinchi vositasini olib yuradi va kosmosdan shamolni o'lchashda mutlaqo yangi yondashuvni qo'llaydi. Aladin deb nomlangan asbob nafaqat lazer transmitterlarini, balki ESA eng katta teleskoplaridan birini orbitaga qo'ydi va atmosferadagi molekulalar va zarrachalar harakati natijasida hosil bo'lgan yorug'lik to'lqin uzunligidagi daqiqalik siljishlarni o'lchaydigan juda sezgir qabul qiluvchilarni keltirib chiqardi. shamol orqali Lidar kontseptsiyasi Lidar kontseptsiyasi Aladin, lazerdan qisqa, kuchli ultrabinafsha nurlarining pulslarini chiqarish orqali ishlaydi va Dopplerni asbobga tarqaladigan juda oz miqdordagi yorug'likdan bu molekulalar va zarrachalarga tushgan vertikal profillarni etkazib berish uchun o'lchaydi. dunyo shamollarining tezligi atmosferaning eng past 30 km. Olimlar va meteorologiya markazlari Aeolus tomonidan ishlab chiqarilgan ma'lumotlardan hayratda qolishganida, birinchi lazer energiyasi xavotirga aylandi - iyun oyida energiya darajasi shamol ma'lumotlari sifatiga putur etkazadigan darajaga tushdi. Tommaso Parrinello, ESA'nin Aeolus vakolatxonasi menejeri, "Birinchi lazerning pasayishi tufayli biz uni o'chirib, ushbu kabi muammoni hal qilishimiz uchun asbob bilan jihozlangan ikkinchi lazerni yoqishga qaror qildik." Ikkinchi lazerga o'tish hiyla ishlatgan ko'rinadi, shuning uchun biz yana ishlayapmiz. Ishonamizki, asbob keyingi yillarda yaxshi holatda qoladi. "

Nitrogen-vacancy Centers Created by Ultrafast Laser Pulses

Laser writing of individual nitrogen-vacancy defects in diamond with near-unity yield. Image: Oxford University

“Quantum technologies” utilize the unique phenomena of quantum superposition and entanglement to encode and process information, with potentially profound benefits to a wide range of information technologies from communications to sensing and computing.

However, a major challenge in developing these technologies is that the quantum phenomena are very fragile, and only a handful of physical systems have been identified in which they survive long enough and are sufficiently controllable to be useful. Atomic defects in materials such as diamond are one such system, but a lack of techniques for fabricating and engineering crystal defects at the atomic scale has limited progress to date.

A team of scientists demonstrate, in a paper published in Optica, the success of the new method to create particular defects in diamonds known as nitrogen-vacancy (NV) color centers. These comprise a nitrogen impurity in the diamond (carbon) lattice located adjacent to an empty lattice site or vacancy.

The NV centers are created by focusing a sequence of ultrafast laser pulses into the diamond, the first of which has an energy high enough to generate vacancies at the center of the laser focus, with subsequent pulses at a lower energy to mobilize the vacancies until one of them binds to a nitrogen impurity and forms the required complex.

The new research was carried out by a team led by Prof Jason Smith in the Department of Materials, University of Oxford, and Dr. Patrick Salter and Prof Martin Booth in the Department of Engineering Science, University of Oxford, in collaboration with colleagues at the University of Warwick. It took place within the research program of NQIT, the Quantum Computing Technology Hub of the UK Quantum Technologies Programme, with support from DeBeers UK who supplied the diamond sample.

Ultrafast lazer impulslari tomonidan yaratilgan azot bo’shatish markazlari.

Olmos tarkibidagi individual azot-bo'shliq nuqsonlarini yaqinlik birligi bilan lazer yordamida yozish. Rasm: Oksford universiteti "Kvant texnologiyalari" kvant superpozitsiyasining noyob hodisalarini axborotni kodlash va ishlov berish uchun ishlatadi, aloqa texnologiyalaridan tortib, sezish va hisoblashgacha ko'plab axborot texnologiyalariga katta foyda keltiradi. Biroq, ushbu texnologiyalarni ishlab chiqishda katta qiyinchilik kvant hodisalari juda mo'rt bo'lib, faqat bir nechta fizik tizimlar aniqlangan bo'lib, ularda ular uzoq umr ko'rishadi va foydali bo'lishi uchun etarli darajada nazorat qilinadi. Olmos kabi materiallarning atom nuqsonlari ana shunday tizimlardan biridir, ammo atom miqyosida to'qish va muhandislik kristalli nuqsonlari hozirgi kunga qadar cheklangan taraqqiyotga ega. Olimlar jamoasi Optica-da nashr etilgan maqolada azot-bo'sh joy (NV) rang markazlari deb nomlanuvchi olmoslarda aniq kamchiliklarni yaratish bo'yicha yangi usulning muvaffaqiyatini namoyish etdilar. Bular bo'sh panjara yoki bo'sh joyga ulashgan olmos (uglerod) panjarasidagi azot aralashmasidan iborat. NV markazlari ultrafast lazer pulslarining ketma-ketligini olmosga yo'naltirish orqali yaratiladi, birinchisi lazer fokusining markazida bo'sh ish o'rinlarini hosil qilish uchun etarlicha yuqori energiya bilan ta'minlanadi va keyinchalik pulslar bo'sh ish joylarini bir martagacha harakatga keltiradi. ulardan azot nopokligi bilan bog'lanadi va kerakli kompleksni hosil qiladi. Yangi tadqiqot Oksford Universitetining Materiallar bo'limida prof. Jeyson Smit va Oksford universiteti muhandislik fanlari bo'limida doktor Patrik Salter va prof Martin But tomonidan olib borildi. Warwick universiteti. Bu NQIT tadqiqot dasturi doirasida, Buyuk Britaniyaning Kvant Texnologiyalari Dasturidagi Quantum Computing Technology Hub, olmos namunasini etkazib bergan DeBeers UK ko'magida amalga oshirildi.

Giant Lasers Crystallize Water Using Shockwaves

In this time-integrated photograph of an X-ray diffraction experiment, giant lasers focus on the water sample, sitting on the front plate of the diagnostic used to record diffraction patterns, to compress it into the superionic phase. Additional laser beams generate an X-ray flash off an iron foil that allows the researchers to take a snapshot of the compress/hot water layer. Diagnostics monitor the time history of the laser pulses and the brightness of the emitted X-ray source. Image: Millot, Coppari, Kowaluk (LLNL)

Scientists from Lawrence Livermore National Laboratory (LLNL) used giant lasers to flash-freeze water into its exotic superionic phase and record X-ray diffraction patterns to identify its atomic structure for the very first time—all in just a few billionths of a second. The findings are reported in Nature.

In 1988, scientists first predicted that water would transition to an exotic state of matter characterized by the coexistence of a solid lattice of oxygen and liquid-like hydrogen—superionic ice—when subjected to the extreme pressures and temperatures that exist in the interior of water-rich giant planets like Uranus and Neptune. These predictions remained in place until 2018, when a team led by scientists from LLNL presented the first experimental evidence for this strange state of water.

Now, the LLNL scientists describe new results. Using laser-driven shockwaves and in-situ X-ray diffraction, they observe the nucleation of a crystalline lattice of oxygen in a few billionths of a second, revealing for the first time the microscopic structure of superionic ice.

Gigant lazerlar amortizator yordamida suvni kristallashtirmoqdalar.

Bu vaqtning o'zida integratsiyalashgan rentgen nurlanish difraksiyasi eksperimentining fotosuratida gigant lazerlar suv namunasiga diqqatni qaratib, diffraksion naqshlarni yozib olish uchun ishlatiladigan diagnostikaning old plastinkasiga joylashtirib, uni superionik fazaga siqib chiqaradi. Qo'shimcha lazer nurlari temir folga yordamida rentgen nurini hosil qiladi, bu esa tadqiqotchilarga kompress / issiq suv qatlamining suratini olish imkonini beradi. Diagnostika lazer pulslarining vaqt tarixini va chiqarilayotgan rentgen manbasining yorqinligini kuzatadi. Tasvir: Millot, Koppari, Kovaluk (LLNL) Lawrence Livermore National Laboratories (LLNL) olimlari o'zining ekzotik superion fazasida suvni muzdan tushirish va uning atom tuzilishini aniqlash uchun rentgen nurlanishining tarqalish namunalarini yozib olish uchun ulkan lazerlardan foydalanganlar. barchasi bir soniyaning atigi bir necha milliarddan birida. Topilmalar haqida Tabiatda xabar berilgan. 1988 yilda olimlar birinchi marta suvning ichki qismida mavjud bo'lgan o'ta bosimli haroratga duchor bo'lganida, kislorod va panjara suyuqligi kabi vodorodli superonik muzlarning birlashishi bilan tavsiflangan ekzotik materiyaga o'tadilar. Uran va Neptun kabi boy gigant sayyoralar. Ushbu bashoratlar 2018 yilga qadar saqlanib qoldi, shunda LLNL olimlari boshchiligidagi guruh suvning bu g'alati holatiga oid birinchi eksperimental dalillarni taqdim etdilar. Es va Endi LLNL olimlari yangi natijalarni bayon qilishdi. Lazer yordamida ishlaydigan zarba to'lqinlari va in-situ rentgen nurlarining tarqalishidan foydalanib, ular sekundining bir necha milliarddan bir qismida kristalli kislorod to'rining nukleatsiyasini kuzatadilar va birinchi marta superionik muzlarning mikroskopik tuzilishini kashf etadilar.

The data also provides further insight into the interior structure of ice giant planets.

“We wanted to determine the atomic structure of superionic water,” said LLNL physicist Federica Coppari, co-lead author of the paper. “But given the extreme conditions at which this elusive state of matter is predicted to be stable, compressing water to such pressures and temperatures and simultaneously taking snapshots of the atomic structure was an extremely difficult task, which required an innovative experimental design.”

The researchers performed a series of experiments at the Omega Laser Facility at the University of Rochester’s Laboratory for Laser Energetics (LLE). They used six giant laser beams to generate a sequence of shockwaves of progressively increasing intensity to compress a thin layer of initially liquid water to extreme pressures (100 to 400 gigapascals (GPa), or one to four million times Earth’s atmospheric pressure) and temperatures (3,000 to 5,000 degrees Fahrenheit).

“We designed the experiments to compress the water so that it would freeze into solid ice, but it was not certain that the ice crystals would actually form and grow in the few billionths of a second that we can hold the pressure-temperature conditions,” said LLNL physicist and co-lead author Marius Millot.

To document the crystallization and identify the atomic structure, the team blasted a tiny iron foil with 16 additional laser pulses to create a hot plasma, which generated a flash of X-rays precisely timed to illuminate the compressed water sample once brought into the predicted stability domain of superionic ice.

Ma'lumotlar, shuningdek, muz gigant sayyoralarining ichki tuzilishi haqida qo'shimcha ma'lumot beradi

. "Biz superionik suvning atom tuzilishini aniqlashni xohladik", dedi LLNL fizigi Federika Koppari, maqolaning hammuallifi. "Ammo ushbu murakkab vaziyat barqaror bo'lishi kutilayotgan o'ta og'ir sharoitda, suvni bunday bosim va haroratga siqib chiqarish va bir vaqtning o'zida atom tuzilishini suratga olish juda murakkab vazifa bo'lib, u innovatsion tajriba dizaynini talab qildi." Tadqiqotchilar Rochester Universitetining Lazer Energetikasi Laboratoriyasida (LLE) Omega lazer qurilmasida bir qator tajribalarni o'tkazdilar. Ular oltita gigant lazer nurlaridan foydalanib, asta-sekin o'sib boruvchi intensivlikdagi zarba to'lqinlarining ketma-ketligini yaratdilar va (masalan, 100 dan 400 gigapaskal (GPa) yoki Yerdan atmosfera bosimidan to'rtdan to'rt million martagacha) va harorat ( Farangeytda 3000-5000 daraja). "Biz suvni qattiq muzga aylanishi uchun siqish uchun tajribalarni ishlab chiqdik, ammo muz kristallari haqiqatan ham sekundning necha milliarddan bir qismida hosil bo'lib, o'sib borishi biz bosim harorati sharoitlarini ushlab tura olmasligi aniq emas edi" % 3D dedi LLNL fizigi va hammuallifi Marius Millot. Kristallanishni hujjatlashtirish va atom tuzilishini aniqlash uchun guruh issiq plazma yaratish uchun 16 ta qo'shimcha lazer pulslari bilan kichkina temir folga bilan portlatdi, bu esa oldindan taxmin qilingan barqarorlikka keltirilgandan so'ng siqilgan suv namunasini aniq yoritib berish uchun rentgen nurlarini yaratdi. superionik muzning domeni.

Perfect Material for Lasers Proposed by Researchers

Light emission resulting from a mutual annihilation of electrons and holes is the operating principle of semiconductor lasers. Image: Elena Khavina/MIPT Press Office

Weyl semimetals are a recently discovered class of materials, in which charge carriers behave the way electrons and positrons do in particle accelerators. Researchers from the Moscow Institute of Physics and Technology and Ioffe Institute in St. Petersburg have shown that these materials represent perfect gain media for lasers. The research findings were published in Physical Review B.

The 21st-century physics is marked by the search for phenomena from the world of fundamental particles in tabletop materials. In some crystals, electrons move as high-energy particles in accelerators. In others, particles even have properties somewhat similar to black hole matter.

MIPT physicists have turned this search inside-out, proving that reactions forbidden for elementary particles can also be forbidden in the crystalline materials known as Weyl semimetals. Specifically, this applies to the forbidden reaction of mutual particle-antiparticle annihilation without light emission. This property suggests that a Weyl semimetal could be the perfect gain medium for lasers.

In a semiconductor laser, radiation results from the mutual annihilation of electrons and the positive charge carriers called holes. However, light emission is just one possible outcome of an electron-hole pair collision. Alternatively, the energy can build up the oscillations of atoms nearby or heat the neighboring electrons. The latter process is called Auger recombination, in honor of the French physicist Pierre Auger.

Auger recombination limits the efficiency of modern lasers in the visible and infrared range, and severely undermines terahertz lasers. It eats up electron-hole pairs that might have otherwise produced radiation. Moreover, this process heats up the device.

For almost a century, researchers have sought a “wonder material” in which radiative recombination dominates over Auger recombination. This search was guided by an idea formulated in 1928 by Paul Dirac. He developed a theory that the electron, which had already been discovered, had a positively charged twin particle, the positron.

Tadqiqotchilar tomonidan taklif qilingan lazerlar uchun mukammal material

Elektron va teshiklarni o'zaro yo'q qilish natijasida hosil bo'ladigan nurlanish yarimo'tkazgich lazerlarining ishlash printsipidir. Rasm: Elena Xavina / MIPT Matbuot ofisi Veyl semimetallari yaqinda kashf etilgan materiallar sinfidir, unda zaryad tashuvchilar elektron va pozitronlarning zarrachalar tezlatgichlarida qanday harakat qilishlarini bilishadi. Moskva Fizika va Texnologiya Instituti va Sankt-Peterburgdagi Loffe Instituti tadqiqotchilari ushbu materiallar lazer uchun yaxshi daromad keltiradigan vosita ekanligini isbotladilar. Tadqiqot natijalari "Fizikaviy sharh B" da e'lon qilindi. 21-asr fizikasi, stol usti materiallarida fundamental zarralar olamidan hodisalarni qidirish bilan ajralib turadi. Ba'zi kristallarda elektronlar tezlatgichlarda yuqori energiyali zarralar kabi harakatlanadi. Boshqalarida zarralar hatto qora tuynuk materiyasiga o'xshash xususiyatlarga ega. MIPT fiziklari bu izlanishni ichkariga o'girib, Veyl semimetallari deb nomlanuvchi kristall materiallarida elementar zarralar uchun taqiqlangan reaktsiyalar ham taqiqlanishi mumkinligini isbotladilar. Xususan, bu o'zaro zarracha-antipartikal zararli yorug'lik chiqarmasdan taqiqlangan reaktsiyaga taalluqlidir. Ushbu xususiyat Weyl semimetali lazerlar uchun mukammal daromad manbai bo'lishi mumkinligini anglatadi. Yarimo'tkazgichli lazerda nurlanish elektronlarning o'zaro yo'q qilinishi va teshiklar deb ataladigan musbat zaryad tashuvchilar natijasida kelib chiqadi. Biroq, yorug'lik chiqarilishi elektron teshik juftligi to'qnashuvining bittagina natijasidir. Shu bilan bir qatorda, energiya yaqin atrofdagi atomlarning tebranishlarini hosil qilishi yoki qo'shni elektronlarni qizdirishi mumkin. Ikkinchi jarayon frantsuz fizigi Per Per Auger sharafiga Auger rekombinatsiyasi deb nomlanadi. Egerning rekombinatsiyasi zamonaviy lazerlarning ko'rinadigan va infraqizil diapazonida samaradorligini cheklaydi va teraherts lazerlarini jiddiy ravishda yo'q qiladi, aks holda nurlanish hosil bo'lishi mumkin bo'lgan elektron teshiklarning juftlarini eydi. Bundan tashqari, bu jarayon qurilmani isitadi. Deyarli bir asr davomida tadqiqotchilar "ajoyib material" izlaydilar, unda radiatsion rekombinatsiya Auger rekombinatsiyasidan ustun turadi. Ushbu qidiruv 1928 yilda Pol Dirak tomonidan ishlab chiqilgan g'oyaga asoslangan edi. U allaqachon kashf qilingan elektron musbat zaryadlangan egizak zarracha, pozitronga ega degan nazariyani ishlab chiqdi.

Cancer Cells Scrutinized with Laser Technology

A scanned image of a grid containing one cancer cell and some blood inside each colored box. The color of the boxes indicates the amount of oxygen dissolved in the blood. Image: Caltech

Devising the best treatment for a patient with cancer requires doctors to know something about the traits of the cancer from which the patient is suffering. But one of the greatest difficulties in treating cancer is that cancer cells are not all the same. Even within the same tumor, cancer cells can differ in their genetics, behavior, and susceptibility to chemotherapy drugs.

Cancer cells are generally much more metabolically active than healthy cells, and some insights into a cancer cell’s behavior can be gleaned by analyzing its metabolic activity. But getting an accurate assessment of these characteristics has proven difficult for researchers. Several methods, including position emission tomography (or PET) scans, fluorescent dyes, and contrasts have been used, but each has drawbacks that limit their usefulness.

Caltech’s Lihong Wang believes he can do better through the use of photoacoustic microscopy (PAM), a technique in which laser light induces ultrasonic vibrations in a sample. Those vibrations can be used to image cells, blood vessels, and tissues.

Wang, Bren Professor of Medical Engineering and Electrical Engineering, is using PAM to improve on an existing technology for measuring the oxygen-consumption rate (OCR) in collaboration with Professor Jun Zou at Texas A&M University. That existing technology takes many cancer cells and places them each into individual “cubbies” filled with blood. Cells with higher metabolisms will use up more oxygen and will lower the blood oxygen level, a process which is monitored by a tiny oxygen sensor placed inside each cubby.

This method, like those previously mentioned, has weaknesses. To get a meaningful sample size of metabolic data for cancer cells would require researchers to embed thousands of sensors into a grid. Additionally, the presence of the sensors within the cubbies can alter the metabolic rates of the cells, causing the collected data to be inaccurate.

Wang’s improved version does away with the oxygen sensors and instead uses PAM to measure the oxygen level in each cubby. He does this with laser light that is tuned to a wavelength that the hemoglobin in blood absorbs and converts into vibrational energy—sound.

Saraton hujayralari lazer texnologiyasi yordamida tekshiriladi

har bir rangli qutining ichida bitta saraton hujayrasi va bir nechta qon mavjud bo'lgan panjara skanerdan o'tkaziladi. Qutilarning rangi qonda erigan kislorod miqdorini ko'rsatadi. Rasm: Caltech Saraton kasalligi bilan og'rigan bemor uchun eng yaxshi davolash usulini ishlab chiqish shifokorlardan bemorni azob chekayotgan saraton belgilari haqida biron bir narsani bilishni talab qiladi. Ammo saraton kasalligini davolashda eng katta qiyinchiliklardan biri shundaki, saraton hujayralari bir xil emas. Hatto bitta o'simta ichida ham saraton hujayralari, ularning genetikasi, xulq-atvori va kimyoterapiya dorilariga sezgirligi bo'yicha farq qilishi mumkin. Saraton hujayralari odatda sog'lom hujayralarga qaraganda ancha faol metabolizmga ega va saraton hujayralarining xatti-harakatlari haqidagi ba'zi ma'lumotlarni uning metabolik faoliyatini tahlil qilish orqali aniqlash mumkin. Ammo bu xususiyatlarni aniq baholash tadqiqotchilar uchun qiyin kechdi. Bir nechta usullar, shu jumladan pozitsion emissiya tomografiyasi (yoki PET) skanerlash, lyuminestsent bo'yoqlar va kontrastlar ishlatilgan, ammo ularning har birida ularning foydaliligini cheklaydigan kamchiliklar mavjud. Caltech kompaniyasi vakili Lixong Vang fotoakustik mikroskopiya (PAM) yordamida lazer nuri namunadagi ultratovush tebranishlarini qo'zg'atadigan texnikadan foydalanish orqali yanada yaxshi ish qila olishiga ishonadi. Ushbu tebranishlardan hujayralarni, qon tomirlarini va to'qimalarni tasvirlash uchun foydalanish mumkin. Tibbiyot va elektrotexnika bo'yicha Bren professori Vang Texas A&M universitetida professor Jun Zou bilan hamkorlikda kislorod iste'moli miqdorini (OCR) o'lchash uchun mavjud texnologiyalarni takomillashtirish uchun PAM-dan foydalanmoqda. Mavjud texnologiya ko'plab saraton hujayralarini oladi va ularning har birini qon bilan to'ldirilgan "kublar" ga joylashtiradi. Metabolizm darajasi yuqori bo'lgan hujayralar ko'proq kislorod iste'mol qiladi va qondagi kislorod miqdorini pasaytiradi, bu jarayon har bir kubga joylashtirilgan mayda kislorod sensori tomonidan nazorat qilinadi. Ushbu usul, ilgari aytib o'tilganlarga o'xshab, kamchiliklarga ega. Saraton hujayralari uchun metabolik ma'lumotlarning aniq hajmini olish tadqiqotchilarga minglab sensorlarni panjara ichiga o'rnatishni talab qiladi. Bundan tashqari, kublar ichidagi sensorlar mavjudligi hujayralarning metabolik tezligini o'zgartirishi mumkin, bu esa to'plangan ma'lumotlarning noto'g'ri bo'lishiga olib keladi. Vangning takomillashtirilgan versiyasi kislorod sezgichlarini yo'q qiladi va uning o'rniga har bir kubikda kislorod miqdorini o'lchash uchun PAMdan foydalanadi. U buni lazer nuri yordamida to'lqin uzunligiga moslashtirib, qonda gemoglobinni yutib, tebranadigan energiya-tovushga aylantiradi.

Spin Lasers Enable Rapid Data Transfer

Markus Lindemann is working on the development of ultrafast spin lasers as part of his doctoral thesis. Image: © RUB, Kramer

So-called spin lasers may potentially accelerate data transfer in optical fiber cables to a considerable extent, while reducing energy consumption at the same time.

Engineers at Ruhr-Universität Bochum have developed a novel concept for rapid data transfer via optical fiber cables. In current systems, a laser transmits light signals through the cables and information is coded in the modulation of light intensity. The new system, a semiconductor spin laser, is based on a modulation of light polarization instead.

Published on April 3, 2019, in the journal Nature, the study demonstrates that spin lasers have the capacity of working at least five times as fast as the best traditional systems, while consuming only a fraction of energy. Unlike other spin-based semiconductor systems, the technology potentially works at room temperature and doesn’t require any external magnetic fields.

The Bochum team at the Chair of Photonics and Terahertz Technology implemented the system in collaboration with colleagues from Ulm University and the University at Buffalo.

Due to physical limitations, data transfer that is based on a modulation of light intensity without utilizing complex modulation formats can only reach frequencies of around 40 to 50 gigahertz. In order to achieve this speed, high electrical currents are necessary.

“It’s a bit like a Porsche where fuel consumption dramatically increases if the car is driven fast,” says Professor Martin Hofmann, one of the engineers from Bochum. “Unless we upgrade the technology soon, data transfer and the Internet are going to consume more energy than we are currently producing on Earth.”

Together with Dr. Nils Gerhardt and PhD student Markus Lindemann, Martin Hofmann is therefore researching into alternative technologies.

Spin lazerlari tezkor ma'lumotlarni uzatishni ta'minlaydi

Markus Lindemann doktorlik dissertatsiyasi doirasida ultrafast spin lazerlarini ishlab chiqish ustida ishlamoqda. Rasm: © RUB, Kramer Spin lazer deb ataladigan narsalar optik tolali kabellarda ma'lumot uzatishni sezilarli darajada tezlashtirishi mumkin va shu bilan birga energiya sarfini kamaytiradi. Ruhr-Universität Bochum muhandislari optik tolali kabellar orqali ma'lumotlarni tezkor uzatish uchun yangi kontseptsiyani ishlab chiqdilar. Amaldagi tizimlarda lazer yorug'lik signallarini kabellar orqali uzatadi va ma'lumotlar yorug'lik zichligi modulyatsiyasida kodlanadi. Yangi tizim, yarimo'tkazgichli spin lazer, uning o'rniga yorug'lik polarizatsiyasining modulyatsiyasiga asoslangan. Tabiat jurnalida 2019 yil 3 aprelda nashr etilgan tadqiqot shuni ko'rsatadiki, spin lazerlari eng yaxshi an'anaviy tizimlardan kamida besh baravar tez ishlash qobiliyatiga ega va shu bilan birga energiya ozgina qismini sarflaydi. Spin asosidagi yarimo'tkazgich tizimlaridan farqli o'laroq, texnologiya xona haroratida ishlaydi va tashqi magnit maydonlarni talab qilmaydi. Fotonika va Teraherts texnologiyalari kafedrasidagi Bochum jamoasi Ulm universiteti va Buffalo universiteti hamkasblari bilan hamkorlikda tizimni joriy qildi. Jismoniy imkoniyatlar cheklanganligi sababli, murakkab modulyatsiya formatlarini ishlatmasdan yorug'lik intensivligini modulyatsiyasiga asoslangan ma'lumotlarni uzatish faqat 40-50 gigagertsgacha bo'lgan chastotalarga erishishi mumkin. Ushbu tezlikka erishish uchun yuqori elektr toklari kerak. "Bu Porsche-ga o'xshaydi, u erda avtomobil tez boshqarilsa yoqilg'i iste'moli keskin ortadi", deydi Bochum muhandislaridan biri professor Martin Xofmann. "Agar biz tez orada texnologiyani yangilamasak, ma'lumotlar uzatish va Internet hozirda Yerda ishlab chiqarayotganimizdan ko'proq energiya sarflaydi." Doktor Nils Gerxardt va doktorant Markus Lindemann bilan birgalikda Martin Xofmann muqobil texnologiyalar bo'yicha izlanishlar olib bormoqda.

New Technique Improves Laser-material Interaction

Illustration of the model used in the picosecond-pulse laser ablation studies. The model was developed in the multi-physics radiation hydrodynamic code HYDRA. The illustration shows a 1D version of the model along the central axis of the laser beam, which was utilized to study material response in isolation from 3D geometric effects.

Using ultrashort laser pulses lasting a few picoseconds (trillionths of a second), Lawrence Livermore National Laboratory (LLNL) researchers have discovered an efficient mechanism for laser ablation (material removal) that could help pave the way to the use of lower-energy, less costly lasers in many industrial laser processing applications.

The new method, reported in a Journal of Applied Physics paper published online, uses short-wavelength, high-fluence (energy per unit area) laser pulses to drive shock waves that melt the target material. After the passage of the shock wave, the melt layer is placed under tension during a process known as relaxation, ultimately leading to the ejection of material through cavitation (unstable bubble growth).

The researchers used a combination of experiments and enhanced computer simulations in a previously unexplored range of laser energies and wavelengths to study picosecond laser pulse ablation of aluminum, stainless steel and silicon. Their findings show that ultraviolet (UV) picosecond pulses at fluences above 10 joules per square centimeter (J/cm2) can remove more material with less energy than longer-wavelength pulses.

“We discovered that this range above 10 joules per square centimeter, particularly for UV laser pulses, was behaving very differently than lower fluences and longer wavelengths,” said Jeff Bude, NIF & Photon Science deputy principal associate director for Science & Technology.

“The removal rate jumps when you go beyond 10 joules per square centimeter, and especially for the UV light,” Bude said. “At the same time the jump in the removal is accompanied by an increase in the removal efficiency—a reduction in the amount of energy required to remove a given volume of material.

“That was really intriguing to us; it suggested that maybe there’s a different mechanism going on here. So we decided picosecond laser ablation would provide a good test case to probe ablation physics in a regime that was not well understood.”

Yangi texnika lazerli materiallarning o'zaro ta'sirini yaxshilaydi

Pikosekond-puls lazerli ablasyon tadqiqotlarida ishlatiladigan modelning illyustratsiyasi. Model HYDRA ko'p fizikaviy nurlanish gidrodinamik kodida ishlab chiqilgan. Rasmda lazer nurining markaziy o'qi bo'ylab modelning 1D versiyasi ko'rsatilgan, u 3D geometrik effektlardan ajratilgan holda materialning javobini o'rganish uchun ishlatilgan. Bir necha pikosekundlarga (soniyasiga trilliondan ko'p) davom etadigan ultrashort lazer pulslaridan foydalangan holda, Lawrence Livermore National Laboratories (LLNL) tadqiqotchilari lazer ablasiyasining (mexanik tozalash) samarali mexanizmini topdilar, bu esa kam energiya sarflashga yo'l ochishi mumkin edi. Ko'p sanoat lazerni qayta ishlash dasturlarida qimmatbaho lazerlar. Internetda chop etilgan "Amaliy fizika" jurnalida e'lon qilingan yangi usul, maqsadli materialni eritib yuboradigan zarba to'lqinlarini qo'zg'atish uchun qisqa to'lqin uzunligi, yuqori oqim (har bir maydon uchun energiya) lazer impulslaridan foydalanadi. Shok to'lqini o'tgandan so'ng, eritma qatlami bo'shashish deb nomlanuvchi jarayon davomida kuchlanish ostida joylashadi va natijada kavitatsiya orqali materialning chiqib ketishiga olib keladi (pufakchaning beqaror o'sishi). Tadqiqotchilar alyuminiy, zanglamaydigan po'lat va kremniyning pikosekond lazerli pulsatsiyasini o'rganish uchun ilgari o'rganilmagan lazer energiyalari va to'lqin uzunliklarida tajribalar va takomillashtirilgan kompyuter simulyatsiyalaridan foydalandilar. Ularning kashfiyotlari ultrabinafsha (UV) pikosekond pulslarining kvadrat santimetrga 10 dyuymdan (J / sm2) oshib ketganda ko'proq to'lqin uzunlikdagi impulslarga qaraganda kamroq energiya sarflashi mumkinligini ko'rsatdi. "Biz aniqladikki, bu kvadrat santimetrga 10 dyuymdan oshadigan nurlar, ayniqsa UB lazer pulslari uchun, past oqimlardan va uzunroq to'lqin uzunligidan farq qiladi", dedi Jeff Bude, NIF va Photon Science ilmiy va texnologiya bo'yicha bosh direktor o'rinbosari o'rinbosari. "Bir kvadrat santimetr uchun 10 jouldan oshib ketganda, ayniqsa, UB nurlari uchun, olib tashlash darajasi ko'tariladi", dedi Bude. "Shu bilan birga, olib tashlashning sakrashi samarani oshirish bilan birga keladi - ma'lum hajmdagi materialni olib tashlash uchun talab qilinadigan energiya miqdorini kamaytirish." Bu bizni juda qiziqtirdi; ehtimol bu erda boshqa mexanizm davom etayotgan bo'lishi mumkin. Shunday qilib, biz pikosekundli lazerli ablasyon ablasyon fizikasini yaxshi tushunilmagan rejimda sinab ko'rish uchun yaxshi sinov bo'ladi deb qaror qildik. "

Researchers Develop New Form of Laser for Sound

In the newest issue of Nature Photonics, researchers from RIT and University of Rochester propose and demonstrate a phonon laser using an optically levitated nanoparticle. Image: Michael Osadciw, University of Rochester illustration

The optical laser has grown to a $10 billion global technology market since it was invented in 1960, and has led to Nobel prizes for Art Ashkin for developing optical tweezing and Gerard Mourou and Donna Strickland for work with pulsed lasers.

Now a Rochester Institute of Technology researcher has teamed up with experts at the University of Rochester to create a different kind of laser—a laser for sound, using the optical tweezer technique invented by Ashkin.

In the newest issue of Nature Photonics, the researchers propose and demonstrate a phonon laser using an optically levitated nanoparticle. A phonon is a quantum of energy associated with a sound wave and optical tweezers test the limits of quantum effects in isolation and eliminates physical disturbances from the surrounding environment. The researchers studied the mechanical vibrations of the nanoparticle, which is levitated against gravity by the force of radiation at the focus of an optical laser beam.

“Measuring the position of the nanoparticle by detecting the light it scatters, and feeding that information back into the tweezer beam allows us to create a laser-like situation,” said Mishkat Bhattacharya, associate professor of physics at RIT and a theoretical quantum optics researcher. “The mechanical vibrations become intense and fall into perfect sync, just like the electromagnetic waves emerging from an optical laser.”

Because the waves emerging from a laser pointer are in sync, the beam can travel a long distance without spreading in all directions—unlike light from the sun or from a light bulb. In a standard optical laser the properties of the light output are controlled by the material from which the laser is made. Interestingly, in the phonon laser the roles of light and matter are reversed—the motion of the material particle is now governed by the optical feedback.

“We are very excited to see what the uses of this device are going to be—especially for sensing and information processing given that the optical laser has so many, and still evolving, applications,” said Bhattacharya.

He also said the phonon laser promises to enable the investigation of fundamental quantum physics, including engineering of the famous thought experiment of Schrödinger’s cat, which can exist at two places simultaneously.

Tadqiqotchilar tovush uchun lazerning yangi shaklini ishlab chiqishdi

Tabiat fotonikasining yangi sonida, RIT va Rochester universiteti tadqiqotchilari optikadan chiqarilgan nanopartikul yordamida fonon lazerini taklif qilishadi va namoyish etishadi. Rasmlar: Maykl Osadciw, Rochester universiteti rasmlari Optik lazer 1960 yilda kashf qilinganidan beri 10 milliard dollarga teng global texnologiya bozorida o'sdi va Art Ashkin uchun Nobel mukofotlariga sazovor bo'ldi, u optik cımbızlığı va Jerar Mouru va Donna Striklend bilan ishlash uchun. impulsli lazerlar. Endi Rochester Texnologiyalar Instituti tadqiqotchisi Ashkin tomonidan ixtiro qilingan optik cımbız texnikasidan foydalanib, ovoz uchun lazer-lazerning boshqa turini yaratish uchun Rochester universiteti mutaxassislari bilan birlashdi. Nature Photonics-ning yangi sonida tadqiqotchilar opton levitlangan nanopartikuldan foydalanib, fonon lazerini taklif qilishadi va namoyish etishadi. Fonon - bu tovush to'lqini bilan bog'liq bo'lgan kvant energiyasidir va optik cımbızlar kvant effektlarining chegaralarini izolyatsiyada sinab ko'radi va atrofdagi muhitdan jismoniy buzilishlarni yo'q qiladi. Tadqiqotchilar optik lazer nurlari markazida nurlanish kuchi bilan tortishish kuchi bilan tortib olinadigan nano-zarrachaning mexanik tebranishlarini o'rganishdi. "Nanobartikulning o'rnini o'lchab turgan yorug'likni aniqlash va bu ma'lumotni cımbız nuriga qaytarish bizga lazerga o'xshash vaziyatni yaratishga imkon beradi", dedi MITKAT Battacharya, RIT fizika professori va nazariy kvant optikasi tadqiqotchisi. . "Mexanik tebranishlar kuchayadi va optik lazerdan kelib chiqqan elektromagnit to'lqinlar singari mukammal sinxronlashuvga aylanadi." Lazer ko'rsatkichidan kelib chiqadigan to'lqinlar bir-biriga uyg'un bo'lganligi sababli, nur barcha yo'nalishlarda tarqalmasdan uzoq masofani bosib o'tishi mumkin - quyoshdan yoki lampochkadan farqli o'laroq. Standart optik lazerda yorug'lik chiqishining xususiyatlari lazer qilingan material tomonidan boshqariladi. Qizig'i shundaki, fonon lazerida yorug'lik va materiyaning rollari teskari - material zarralari harakati optik teskari aloqa orqali boshqariladi. "Biz ushbu qurilmaning ishlatilishi, ayniqsa optik lazer juda ko'p va hali ham rivojlanib borayotgan ilovalar mavjudligini hisobga olsak, sezish va ma'lumotlarga ishlov berish uchun nima bo'lishini ko'rishdan juda xursandmiz", dedi Bxattacharya. Uning so'zlariga ko'ra, fonon lazer fundamental kvant fizikasini, shu bilan birga bir vaqtning o'zida ikkita joyda mavjud bo'lishi mumkin bo'lgan Shrödinger mushukining taniqli fikrlash tajribasini yaratishga imkon beradi.