Laser yothamanga kwambiri yobwerezabwereza

Laser yothamanga kwambiri yobwerezabwereza

Mu dziko la microscopic lomwe kuwala ndi chinthu zimagwirira ntchito, ma ultra-high repetition rate pulses (UHRPs) amagwira ntchito ngati olamulira olondola a nthawi - amasinthasintha nthawi zoposa biliyoni imodzi pamphindikati (1GHz), kujambula zala za maselo a khansa pogwiritsa ntchito spectral imaging, kunyamula deta yambiri mu optical fiber communication, ndikulinganiza ma wavelength coordinates a nyenyezi mu telescopes. Makamaka pakudumpha kwa dimension ya lidar, ma terahertz ultra-high repetition rate pulsed lasers (100-300 GHz) akukhala zida zamphamvu zolowera mu interference layer, kusinthanso malire a three-dimensional perception ndi spatiotemporal manipulation power pamlingo wa photon. Pakadali pano, kugwiritsa ntchito ma microstructures opangidwa, monga ma micro-ring cavities omwe amafunikira nanoscale processing accuracy kuti apange four-wave mixing (FWM), ndi njira imodzi yayikulu yopezera ma ultra-high repetition rate optical pulses. Asayansi akuyang'ana kwambiri kuthetsa mavuto a uinjiniya pakukonza ma ultra-fine structures, vuto la frequency tuning panthawi yoyambitsa pulse, komanso vuto la conversion efficiency pambuyo pa kupanga pulse. Njira ina ndikugwiritsa ntchito ulusi wosakhala wolunjika kwambiri ndikugwiritsa ntchito mphamvu ya kusakhazikika kwa modulation kapena mphamvu ya FWM mkati mwa laser cavity kuti tisangalatse UHRPs. Pakadali pano, tikufunikirabe "chosintha nthawi" chaluso kwambiri.

Njira yopangira UHRP mwa kubaya ma pulse othamanga kwambiri kuti alimbikitse mphamvu ya FWM yotayika imafotokozedwa ngati "kuipitsa kwa ultrafast". Mosiyana ndi njira yopangira ma microring cavity yomwe yatchulidwa pamwambapa yomwe imafuna kupopera kosalekeza, kusintha kolondola kwa kutseka kuti kulamulire kupanga ma pulse, ndikugwiritsa ntchito njira zosalunjika kwambiri kuti muchepetse malire a FWM, "kuyatsa" kumeneku kumadalira mphamvu yayikulu ya ma pulse othamanga kwambiri kuti alimbikitse FWM mwachindunji, ndipo pambuyo pa "kuyatsa", Kukwaniritsa UHRP yodziyimira yokha.

Chithunzi 1 chikuwonetsa njira yayikulu yopezera kukhazikika kwa pulse kutengera kukweza kwa pulse ya mbewu mwachangu kwambiri kwa ma cavities a mphete ya ulusi wofalikira. Mpweya wa mbewu waufupi wolowetsedwa kunja (nthawi T0, kubwerezabwereza kwa F) umagwira ntchito ngati "gwero loyatsira" kuti lilimbikitse mphamvu ya pulse yamphamvu kwambiri mkati mwa cavity yofalikira. Gawo lopeza la mkati mwa maselo limagwira ntchito mogwirizana ndi chopanga ma spectral kuti lisinthe mphamvu ya pulse ya mbewu kukhala yankho lofanana ndi chisakanizo kudzera mu regulation yolumikizana mu nthawi-frequency domain. Njirayi imadutsa malire a kupompa kosalekeza kwachikhalidwe: pulse ya mbewu imazima ikafika pamlingo wa FWM wofalikira, ndipo cavity yofalikira imasunga mkhalidwe wodzikonzera wa pulse kudzera mu dynamic balance of gain and loss, ndi pulse repetition frequency kukhala Fs (yofanana ndi intrinsic frequency FF ndi nthawi T ya cavity).

Kafukufukuyu adachitanso kutsimikizira kwa chiphunzitso. Kutengera magawo omwe adagwiritsidwa ntchito mu kukhazikitsidwa koyesera komanso ndi 1pslaser yothamanga kwambiriMonga gawo loyambirira, kuyerekezera manambala kunachitika pa njira yosinthira nthawi ya pulse ndi mafupipafupi mkati mwa laser cavity. Zinapezeka kuti pulse idadutsa magawo atatu: kugawanika kwa pulse, kusinthasintha kwa pulse periodic, ndi kugawa kwa pulse mofanana mu laser cavity yonse. Zotsatirazi za manambala zimatsimikiziranso mokwanira makhalidwe odzikonzera okha alaser ya kugunda kwa mtima.

Mwa kuyambitsa mphamvu yosakanikirana ya mafunde anayi mkati mwa mphero ya ulusi wofalikira kudzera mu kuyatsa kwa pulse ya mbewu mwachangu kwambiri, kupanga ndi kukonza ma pulse a sub-THZ ultra-high repetition frequency (kutulutsa kokhazikika kwa mphamvu ya 0.5W mbewu itazimitsidwa) kunakwaniritsidwa bwino, kupereka mtundu watsopano wa gwero la kuwala kwa munda wa lidar: Kubwerezabwereza kwa sub-THZ level yake kumatha kukulitsa kutsimikiza kwa mtambo wa point kufika pa mulingo wa millimeter. Mbali yodziyimira yokha ya pulse imachepetsa kwambiri kugwiritsa ntchito mphamvu ya dongosolo. Kapangidwe ka ulusi wonse kamatsimikizira kugwira ntchito kokhazikika kwambiri mu gulu loteteza maso la 1.5 μm. Poyang'ana mtsogolo, ukadaulo uwu ukuyembekezeka kuyendetsa kusintha kwa lidar yokwezedwa ndi galimoto kupita ku miniaturization (kutengera ma MZI micro-filters) ndi kuzindikira kwakutali (kukula kwa mphamvu kufika pa > 1W), ndikusinthira ku zofunikira za kuzindikira za malo ovuta kudzera mu kuyatsa kogwirizana kwa mafunde ambiri komanso malamulo anzeru.