Chowunikira chithunzi cha bipolar two-dimensional avalanche

Matenda a bipolar awiri-dimensionalchowunikira zithunzi cha chipale chofewa

Chowunikira mafunde a bipolar two-dimensional avalanche (Chowunikira zithunzi cha APD) imapeza phokoso lotsika kwambiri komanso kuzindikira kukhudzidwa kwakukulu

Kuzindikira ma photon ochepa kapena ma photon amodzi omwe ali ndi mphamvu yowonjezereka kuli ndi njira zofunika zogwiritsira ntchito m'magawo monga kujambula kuwala kofooka, kuzindikira kutali ndi telemetry, komanso kulumikizana kwa quantum. Pakati pawo, chowunikira zithunzi cha avalanche (APD) chakhala njira yofunika kwambiri yofufuzira zida zamagetsi chifukwa cha mawonekedwe ake ang'onoang'ono, magwiridwe antchito apamwamba komanso kuphatikiza kosavuta. Chiŵerengero cha signal-to-noise (SNR) ndi chizindikiro chofunikira cha chowunikira zithunzi cha APD, chomwe chimafuna kuchuluka kwakukulu komanso mphamvu yamdima yochepa. Kafukufuku wokhudza kuyanjana kwa van der Waals pazinthu zamitundu iwiri (2D) akuwonetsa kuthekera kwakukulu pakupanga ma APD apamwamba. Ofufuza ochokera ku China adasankha zinthu za bipolar two-dimensional semiconductor WSe₂ ngati chinthu chowunikira zithunzi ndipo adakonza bwino APD photodetector yokhala ndi kapangidwe ka Pt/WSe₂/Ni komwe kali ndi ntchito yabwino kwambiri yofananira, kuti athetse vuto la phokoso la gain lochokera ku chowunikira zithunzi cha APD chachikhalidwe.

Gulu lofufuza linapereka lingaliro la chipangizo chowunikira kuwala kwa avalanche kutengera kapangidwe ka Pt/WSe₂/Ni, chomwe chinapeza kuzindikira kwamphamvu kwambiri kwa zizindikiro zofooka kwambiri pamlingo wa fW kutentha kwa chipinda. Anasankha chipangizo cha semiconductor cha miyeso iwiri WSe₂, chomwe chili ndi mphamvu zamagetsi zabwino kwambiri, ndipo anaphatikiza zipangizo za Pt ndi Ni electrode kuti apange bwino mtundu watsopano wa chipangizo chowunikira kuwala kwa avalanche. Mwa kukonza bwino momwe ntchito ikuyendera pakati pa Pt, WSe₂ ndi Ni, njira yonyamulira idapangidwa yomwe ingatseke bwino zonyamulira zakuda pomwe imalola zonyamulira zopangidwa ndi photo kuti zidutse. Njirayi imachepetsa kwambiri phokoso lochulukirapo lomwe limayambitsidwa ndi ionization ya carrier impact, zomwe zimathandiza chipangizo chowunikira kuwala kupeza kuzindikira kwamphamvu kwambiri kwa chizindikiro cha kuwala pamlingo wotsika kwambiri wa phokoso.

Kenako, kuti afotokoze bwino momwe zimakhalira ndi mphamvu ya avalanche yomwe imabwera chifukwa cha mphamvu yamagetsi yofooka, ofufuzawo poyamba adayesa momwe ntchito za zitsulo zosiyanasiyana zimagwirizanirana ndi WSe₂. Zida zingapo zachitsulo-semiconductor-metal (MSM) zokhala ndi ma electrode osiyanasiyana achitsulo zidapangidwa ndipo mayeso oyenerera adachitika pa izo. Kuphatikiza apo, pochepetsa kufalikira kwa carrier avalanche isanayambe, kusakhazikika kwa impact ionization kumatha kuchepetsedwa, motero kuchepetsa phokoso. Chifukwa chake, mayeso oyenerera adachitika. Kuti awonetse bwino kupambana kwa Pt/WSe₂/Ni APD pankhani ya nthawi yoyankha, ofufuza adawunikanso bandwidth ya -3 dB ya chipangizocho pansi pa mitundu yosiyanasiyana ya photoelectric gain.

Zotsatira za kafukufukuyu zikusonyeza kuti chowunikira cha Pt/WSe₂/Ni chikuwonetsa mphamvu yofanana ndi phokoso lotsika kwambiri (NEP) kutentha kwa chipinda, komwe ndi 8.07 fW/√Hz yokha. Izi zikutanthauza kuti chowunikirachi chimatha kuzindikira zizindikiro zofooka kwambiri. Kuphatikiza apo, chipangizochi chimatha kugwira ntchito mokhazikika pa 20 kHz modulation frequency ndi gain yayikulu ya 5×10⁵, kuthetsa bwino zovuta zaukadaulo za zowunikira zachikhalidwe za photovoltaic zomwe zimakhala zovuta kulinganiza gain yayikulu ndi bandwidth. Mbali iyi ikuyembekezeka kuipereka zabwino zazikulu mu ntchito zomwe zimafuna gain yayikulu komanso phokoso lochepa.

Kafukufukuyu akuwonetsa ntchito yofunika kwambiri ya uinjiniya wa zinthu ndi kukonza mawonekedwe pakukweza magwiridwe antchito ama photodetectorsKudzera mu kapangidwe kabwino ka ma electrode ndi zipangizo zokhala ndi miyeso iwiri, mphamvu yoteteza zinthu zonyamula zakuda yapezeka, kuchepetsa kwambiri kusokoneza phokoso ndikupititsa patsogolo luso lozindikira.

Kugwira ntchito kwa chipangizochi sikungowoneka kokha m'makhalidwe a magetsi, komanso kumawonjezera mwayi wogwiritsa ntchito. Chifukwa chotseka bwino mphamvu yamdima kutentha kwa chipinda komanso kuyamwa bwino kwa zinthu zopangidwa ndi zithunzi, chipangizochi ndi choyenera kwambiri kuzindikira zizindikiro zofooka za kuwala m'magawo monga kuyang'anira chilengedwe, kuyang'ana zakuthambo, ndi kulumikizana kwa kuwala. Kupambana kwa kafukufukuyu sikungopereka malingaliro atsopano pakupanga zida zowunikira zithunzi zotsika, komanso kumapereka maumboni atsopano a kafukufuku wamtsogolo ndi chitukuko cha zida zamagetsi zamagetsi zogwira ntchito kwambiri komanso zochepa.