Fa'idodi da mahimmancin fim ɗin lithium niobate na bakin ciki a cikin fasahar photon microwave hadedde
Fasahar photon Microwaveyana da abũbuwan amfãni daga babban aiki bandwidth, da karfi a layi daya iya aiki da kuma low watsa asarar, wanda yana da yuwuwar ya karya ƙwaƙƙwarar fasaha na tsarin microwave na gargajiya da kuma inganta aikin kayan aikin lantarki na soja kamar radar, yakin lantarki, sadarwa da aunawa sarrafawa. Koyaya, tsarin photon na microwave wanda ya dogara da na'urori masu hankali yana da wasu matsaloli kamar girman girma, nauyi mai nauyi da rashin kwanciyar hankali, wanda ke da matuƙar taƙaita aikace-aikacen fasahar photon microwave a sararin samaniya da dandamali na iska. Saboda haka, haɗaɗɗen fasahar photon na microwave yana zama muhimmin tallafi don karya aikace-aikacen photon na microwave a cikin tsarin bayanan lantarki na soja da ba da cikakkiyar wasa ga fa'idodin fasahar photon microwave.
A halin yanzu, fasahar haɗin kai ta hanyar SI da fasahar haɗin kai ta hoto ta INP ta ƙara girma bayan shekaru da yawa na ci gaba a fagen sadarwa na gani, kuma an saka kayayyaki da yawa a kasuwa. Koyaya, don aikace-aikacen photon na microwave, akwai wasu matsaloli a cikin waɗannan nau'ikan fasahar haɗin gwiwar photon guda biyu: alal misali, ƙirar lantarki da ba ta dace ba na Si modulator da InP modulator ya saba wa babban layin layi da manyan halaye masu ƙarfi da microwave ke bi. fasahar photon; Misali, Silicon Tantancewar na'urar da ke gane canjin hanyar gani, ko ta dogara da tasirin thermal-optical, tasirin piezoelectric, ko tasirin watsawar allura mai ɗaukar nauyi, yana da matsalolin jinkirin saurin sauyawa, amfani da wutar lantarki da amfani da zafi, wanda ba zai iya saduwa da sauri ba. duban katako da manyan sikelin sikelin microwave photon aikace-aikace.
Lithium niobate ya kasance zaɓi na farko don babban guduna'ura mai aiki da karfin ruwa na lantarkikayan saboda kyakkyawan tasirin sa na lantarki na linzamin kwamfuta. Koyaya, lithium niobate na gargajiyaelectro-Optical modulatoran yi shi da babban kayan kristal na lithium niobate, kuma girman na'urar yana da girma sosai, wanda ba zai iya biyan buƙatun fasahar fasahar photon microwave hadedde ba. Yadda za a haɗa kayan lithium niobate tare da madaidaicin electro-optical coefficient cikin haɗaɗɗen tsarin fasahar photon na microwave ya zama burin masu binciken da suka dace. A cikin 2018, ƙungiyar bincike daga Jami'ar Harvard da ke Amurka ta fara ba da rahoton fasahar haɗin kai ta photonic dangane da ƙaramin fim na lithium niobate a cikin Nature, saboda fasahar tana da fa'idodin babban haɗin gwiwa, babban bandwidth na gani na lantarki, da babban layin wutar lantarki. - Tasirin gani, da zarar an ƙaddamar da shi, nan da nan ya haifar da kulawar ilimi da masana'antu a fagen haɗin gwiwar photonic da microwave photonics. Daga mahangar aikace-aikacen photon na microwave, wannan takarda tana duba tasiri da mahimmancin fasahar haɗin gwiwar photon dangane da siriri fim lithium niobate akan haɓaka fasahar photon microwave.
Bakin fim lithium niobate abu da bakin ciki fimlithium niobate modulator
A cikin shekaru biyu da suka wuce, wani sabon nau'in kayan lithium niobate ya fito, wato, fim ɗin lithium niobate an cire shi daga babban lithium niobate crystal ta hanyar "yankakken ion" kuma an haɗa shi da Si wafer tare da silica buffer Layer zuwa silica. siffan LNOI (LiNbO3-On-Insulator) abu [5], wanda ake kira sikirin fim lithium niobate abu a cikin wannan takarda. Ridge waveguides da tsayi fiye da 100 nanometers za a iya etched a kan bakin ciki fim lithium niobate kayan ta inganta bushe etching tsari, da kuma tasiri refractive index bambanci na waveguides kafa zai iya kai fiye da 0.8 (nisa mafi girma fiye da refractive index bambanci na gargajiya). lithium niobate waveguides na 0.02), kamar yadda aka nuna a Hoto 1. Ƙarfin ƙuntataccen raƙuman raƙuman ruwa yana sa ya zama sauƙi don daidaita filin haske tare da filin microwave lokacin zayyana na'ura. Don haka, yana da fa'ida don cimma ƙananan ƙarfin wutar lantarki na rabin-ƙara da babban bandwidth na daidaitawa a cikin ɗan gajeren tsayi.
Bayyanar ƙarancin asara lithium niobate submicron waveguide yana karya ƙwanƙarar babban ƙarfin lantarki na al'adar lithium niobate electro-optic modulator. Za a iya rage tazarar lantarki zuwa ~ 5 μm, kuma abin da ke tsakanin filin lantarki da filin yanayin gani yana ƙaruwa sosai, kuma vπ · L yana raguwa daga fiye da 20 V · cm zuwa ƙasa da 2.8 V · cm. Sabili da haka, a ƙarƙashin irin ƙarfin wutar lantarki na rabin-wave, za a iya rage tsawon na'urar sosai idan aka kwatanta da na'ura na gargajiya. A lokaci guda, bayan inganta ma'auni na nisa, kauri da tazara na lantarki na igiyar tafiya, kamar yadda aka nuna a cikin adadi, na'urar na'ura na iya samun damar yin amfani da ultra-high modulation bandwidth fiye da 100 GHz.
Fig.1 (a) rarraba yanayin da aka ƙididdigewa da (b) hoton giciye-ɓangaren LN waveguide
Fig.2 (a) Waveguide da tsarin lantarki da (b) coreplate na LN modulator
Kwatanta na'urorin lithium niobate na fim na bakin ciki tare da na'urorin kasuwanci na lithium niobate na gargajiya, masu amfani da siliki da indium phosphide (InP) masu daidaitawa da sauran na'urori masu saurin sauri na lantarki, manyan sigogin kwatancen sun haɗa da:
(1) Samfurin tsawon rabin-wave volt (vπ · L, V·cm), yana auna ingancin na'ura mai daidaitawa, ƙarami ƙimar, mafi girman ingancin daidaitawa;
(2) 3 dB gyare-gyaren gyare-gyare na bandwidth (GHz), wanda ke auna amsawar mai daidaitawa zuwa matsakaicin mita mai girma;
(3) Asarar shigar da gani (dB) a cikin yankin daidaitawa. Ana iya gani daga tebur cewa sikirin fim ɗin lithium niobate modulator yana da fa'ida a bayyane a cikin bandwidth na daidaitawa, wutar lantarki ta rabin-wave, asarar interpolation na gani da sauransu.
Silicon, a matsayin ginshiƙin haɗaɗɗen optoelectronics, an haɓaka shi ya zuwa yanzu, tsarin ya balaga, ƙarancinsa yana ba da gudummawa ga babban haɗin kai na na'urori masu aiki / m, kuma an yi nazari mai zurfi sosai a fagen gani. sadarwa. Na'urar daidaitawa ta lantarki ta siliki ita ce mafi yawan jigilar jigilar kaya, allurar jigilar kaya da tarawar jigilar kaya. Daga cikin su, bandwidth na modulator yana da mafi kyaun tare da madaidaicin digiri mai ɗaukar nauyin ƙaddamarwa, amma saboda rarrabawar filayen filaye ya mamaye tare da rashin daidaituwa na yankin raguwa, wannan tasirin zai gabatar da ɓarna na biyu na rashin daidaituwa da kuma rikice-rikice na tsaka-tsakin tsari na uku. sharuddan, haɗe tare da tasirin ɗaukar mai ɗaukar hoto akan haske, wanda zai haifar da raguwar haɓakar haɓakar haɓakar gani da karkatar da sigina.
InP modulator yana da fitattun tasirin electro-optical, kuma tsarin rijiyar adadi mai yawa na iya gane matsananciyar ƙima da ƙarancin ƙarfin lantarki tare da Vπ · L har zuwa 0.156V · mm. Koyaya, bambance-bambancen firikwensin refractive tare da filin lantarki ya haɗa da madaidaiciyar kalmomi da kalmomin da ba na layi ba, kuma haɓaka ƙarfin filin lantarki zai sa tasirin tsari na biyu ya shahara. Saboda haka, silicon da InP electro-optic modulators suna buƙatar amfani da son rai don samar da haɗin pn lokacin da suke aiki, kuma haɗin pn zai kawo asarar sha ga haske. Koyaya, girman modulator na waɗannan biyun ƙarami ne, girman InP modulator na kasuwanci shine 1/4 na ƙirar LN. Haɓaka haɓakawa mai girma, dacewa da babban yawa da gajeriyar hanyar sadarwar watsawar gani na dijital kamar cibiyoyin bayanai. Tasirin electro-optical na lithium niobate ba shi da tsarin ɗaukar haske da ƙarancin asara, wanda ya dace da daidaituwar nesa mai nisa.sadarwa na ganitare da babban iya aiki da babban kudi. A cikin aikace-aikacen photon na microwave, ma'aunin lantarki-na gani na Si da InP ba su da tushe, wanda bai dace da tsarin photon na microwave ba wanda ke bin babban layi da kuma babban tasiri. Abun lithium niobate ya dace sosai don aikace-aikacen photon na microwave saboda madaidaicin tsarin daidaitawa na lantarki-optic gabaɗaya.
Lokacin aikawa: Afrilu-22-2024