Chiyambi, mtundu wa kuwerengera kwa fotoni mtundu wa avalanche photodetector

Chiyambi, mtundu wa kuwerengera kwa fotonichowunikira chithunzi cha avalanche yolunjika

Ukadaulo wowerengera ma photon ukhoza kukulitsa mokwanira chizindikiro cha photon kuti uthetse phokoso lowerengedwa la zida zamagetsi, ndikulemba kuchuluka kwa ma photon omwe atulutsidwa ndi chowunikira munthawi inayake pogwiritsa ntchito mawonekedwe achilengedwe a chizindikiro chamagetsi chowunikira pansi pa kuwala kofooka, ndikuwerengera zambiri za cholinga choyesedwa malinga ndi mtengo wa foton meter. Kuti azindikire kuwala kofooka kwambiri, mitundu yosiyanasiyana ya zida zomwe zili ndi mphamvu yozindikira ma photon yaphunziridwa m'maiko osiyanasiyana. Photodiode yolimba ya avalanche (Chowunikira zithunzi cha APD) ndi chipangizo chomwe chimagwiritsa ntchito mphamvu yamkati ya photoelectric kuti chizindikire zizindikiro za kuwala. Poyerekeza ndi zipangizo zotsukira, zipangizo zolimbitsa thupi zili ndi ubwino woonekeratu pa liwiro loyankha, kuchuluka kwa mdima, kugwiritsa ntchito mphamvu, kuchuluka kwa voliyumu ndi mphamvu ya maginito, ndi zina zotero. Asayansi achita kafukufuku wozikidwa pa ukadaulo wowerengera zithunzi za APD zolimbitsa thupi.

Chipangizo chowunikira zithunzi cha APDIli ndi njira ziwiri zogwirira ntchito za Geiger mode (GM) ndi linear mode (LM), ukadaulo wamakono wowerengera ma photon a APD umagwiritsa ntchito chipangizo cha Geiger mode APD. Zipangizo za Geiger mode APD zimakhala ndi mphamvu yayikulu pamlingo wa single photon komanso liwiro lalikulu la ma nanoseconds makumi kuti zipeze kulondola kwa nthawi yayitali. Komabe, Geiger mode APD ili ndi mavuto ena monga detector dead time, kuchepa kwa kuzindikira, kufalikira kwakukulu kwa mawu owoneka bwino komanso kusasinthika kwa malo, kotero zimakhala zovuta kukonza kutsutsana pakati pa kuchuluka kwa kuzindikira ndi kuchepa kwa alamu yabodza. Zipangizo za Photon zozikidwa pa near-noiseless high-gain HgCdTe APD zimagwira ntchito mu linear mode, zilibe nthawi yakufa ndi zoletsa za crosstalk, zilibe post-pulse yogwirizana ndi Geiger mode, sizifuna ma quench circuits, zili ndi ultra-high dynamic range, wide and tuning spectral response range, ndipo zimatha kukonzedwa payokha kuti zizindikire bwino komanso kuchuluka kwa kuwerengera kwabodza. Imatsegula gawo latsopano la kugwiritsa ntchito zithunzi zowerengera ma photon a infrared, ndi njira yofunika kwambiri yopangira zida zowerengera ma photon, ndipo ili ndi mwayi waukulu wogwiritsa ntchito mu kuyang'ana zakuthambo, kulumikizana kwa mlengalenga momasuka, kujambula kogwira ntchito komanso kosachitapo kanthu, kutsatira ma fringe ndi zina zotero.

Mfundo yowerengera ma photon mu zipangizo za HgCdTe APD

Zipangizo zowunikira zithunzi za APD zochokera ku zipangizo za HgCdTe zimatha kuphimba mafunde osiyanasiyana, ndipo ma coefficients a ionization a ma elekitironi ndi mabowo ndi osiyana kwambiri (onani Chithunzi 1 (a)). Zimasonyeza njira imodzi yochulukitsa yonyamula mkati mwa mafunde odulidwa a 1.3 ~ 11 µm. Palibe phokoso lochulukirapo (poyerekeza ndi phokoso lochulukirapo FSi~2-3 la zipangizo za Si APD ndi FIII-V~4-5 la zipangizo za banja la III-V (onani Chithunzi 1 (b)), kotero kuti chiŵerengero cha chizindikiro-kwa-phokoso cha zipangizo sichimachepa ndi kuwonjezeka kwa gain, komwe ndi infrared yoyenera.chowunikira zithunzi cha chipale chofewa.

CHITHUNZI 1 (a) Ubale pakati pa chiŵerengero cha impact ionization coefficient cha mercury cadmium telluride material ndi gawo la x la Cd; (b) Kuyerekeza kwa noise factor F yowonjezera ya zida za APD ndi makina osiyanasiyana azinthu

Ukadaulo wowerengera ma photon ndi ukadaulo watsopano womwe ungathe kutulutsa zizindikiro za kuwala kuchokera ku phokoso la kutentha mwa kuthetsa ma pulse a photoelectron opangidwa ndichowunikira zithunziPambuyo polandira photon imodzi. Popeza chizindikiro chotsika chimafalikira kwambiri munthawi, kutulutsa kwa chizindikiro chamagetsi kuchokera ku detector kumakhalanso kwachilengedwe komanso kosiyana. Malinga ndi khalidweli la kuwala kofooka, kukulitsa kwa pulse, kusankhana kwa pulse ndi njira zowerengera digito nthawi zambiri zimagwiritsidwa ntchito kuzindikira kuwala kofooka kwambiri. Ukadaulo wamakono wowerengera ma photon uli ndi zabwino zambiri, monga chiŵerengero chapamwamba cha ma signal-to-noise, kusankhana kwakukulu, kulondola kwambiri kwa muyeso, kukana kugwedezeka, kukhazikika kwa nthawi, ndipo ukhoza kutulutsa deta ku kompyuta mu mawonekedwe a chizindikiro cha digito kuti chisanthulidwe ndi kukonzedwa pambuyo pake, zomwe sizingafanane ndi njira zina zodziwira. Pakadali pano, njira yowerengera ma photon yagwiritsidwa ntchito kwambiri pantchito yoyezera mafakitale ndi kuzindikira kuwala kotsika, monga nonlinear optics, molecular biology, ultra-high resolution spectroscopy, astronomical photometry, muyeso wa kuipitsidwa kwa mpweya, ndi zina zotero, zomwe zimagwirizana ndi kupeza ndi kuzindikira zizindikiro zofooka za kuwala. Chojambulira mafunde cha mercury cadmium telluride avalanche chilibe phokoso lochulukirapo, pamene kuchuluka kwa mafunde kukuwonjezeka, chiŵerengero cha ma signal-to-noise sichikuwola, ndipo palibe nthawi yotayika komanso yoletsa mafunde pambuyo pa kugunda kwa magetsi yokhudzana ndi zida za Geiger avalanche, zomwe ndizoyenera kwambiri kugwiritsidwa ntchito powerengera mafunde, ndipo ndi njira yofunika kwambiri yopangira zida zowerengera mafunde mtsogolo.