Umutima wa Lazeri zikoresha amashanyarazi: Gusobanukirwa PN Junction

Bitewe n’iterambere ryihuse ry’ikoranabuhanga rya optoelectronic, laser za semiconductor zabonye uburyo bwinshi bwo gukoresha mu nzego zitandukanye nko mu itumanaho, ibikoresho by’ubuvuzi, laser ranging, gutunganya inganda, n’ibikoresho by’ikoranabuhanga bikoreshwa n’abaguzi. Ishingiro ry’iri koranabuhanga ni PN junction, ifite uruhare runini—atari isoko y’ibyuka by’urumuri gusa ahubwo no kuba ishingiro ry’imikorere y’igikoresho. Iyi nkuru itanga incamake isobanutse kandi isobanutse y’imiterere, amahame, n’imirimo y’ingenzi y’ihuriro rya PN muri laser za semiconductor.

1. PN Junction ni iki?

Ihuriro rya PN ni ihuriro rikorwa hagati ya semiconductor yo mu bwoko bwa P na semiconductor yo mu bwoko bwa N:

Semiconductor yo mu bwoko bwa P igizwe n'imyanda ifata, nka boron (B), bigatuma imyobo iba ari yo itwara umuriro mwinshi.

Semiconductor yo mu bwoko bwa N irimo imyanda ikomoka ku batanga, nka fosifore (P), bigatuma electron ziba ari zo zitwara ibintu byinshi.

Iyo ibikoresho byo mu bwoko bwa P na N bihujwe, electron ziva mu karere ka N zinjira mu karere ka P, naho imyobo ziva mu karere ka P zigakwirakwira mu karere ka N. Uku gukwirakwira kw'amashanyarazi bitera akarere k'ibura aho electron n'imyobo bihurira, bigasiga irons zifite umuriro zikora amashanyarazi imbere, izwi nka "built-in potential barrier".

2. Uruhare rw'ihuriro rya PN muri lasers

(1) Inshinge zo gutwara ibintu

Iyo laser ikora, aho PN ihurira haba hifashishijwe ingufu zidasanzwe: akarere ka P gahujwe na voltage nziza, naho akarere ka N gahujwe na voltage mbi. Ibi bihagarika ingufu z'amashanyarazi imbere, bigatuma electron n'imyobo bishyirwa mu gace gakora ku ihuriro, aho bishobora kongera kwihuza.

(2) Ibyuka biva mu mucyo: Inkomoko y'Ibyuka biva mu mucyo

Mu gace gakora, electron n'imyobo byatewe birongera bigakora fotoni. Mu ntangiriro, iyi nzira ni iyoherezwa ryihuta, ariko uko ubucucike bwa fotoni bwiyongera, fotoni zishobora gukurura ubundi buryo bwo gusubiranamo kwa electron n'imyobo, zigasohora fotoni z'inyongera zifite icyiciro kimwe, icyerekezo kimwe, n'ingufu zimwe - ibi ni iyoherezwa ryihuta.

Iyi gahunda igize ishingiro rya laser (Light Amplification by Stimulated Emission of Radiation).

(3) Utubo two mu bwonko two mu bwoko bwa Gain and Resonant two mu bwoko bwa Laser Output

Kugira ngo hongerwe imyuka ishyushye, laser za semiconductor zirimo imiyoboro itukura ku mpande zombi z'ihuriro rya PN. Urugero, muri laser zisohora imirasire y'izuba, ibi bishobora kugerwaho hakoreshejwe Distributed Bragg Reflectors (DBRs) cyangwa indorerwamo kugira ngo urumuri rugaragare imbere n'imbere. Iyi gahunda ituma uburebure bw'urumuri bwihariye bwongerwa, amaherezo bigatanga umusaruro wa laser uhamye kandi w'icyerekezo.

3. Imiterere ya PN Junction n'Uburyo bwo kunoza imiterere

Bitewe n'ubwoko bwa laser ya semiconductor, imiterere ya PN ishobora gutandukana:

Heterojunction imwe (SH):
Agace ka P, agace ka N, n'agace gakora bikozwe mu bikoresho bimwe. Agace ko kongeramo ni kagari kandi ntigakora neza cyane.

Heterojunction ebyiri (DH):
Uduce duto tw’urukiramende dushyirwa hagati y’uturere twa P na N. Ibi bigabanya uduce dutwara ibintu ndetse n’udufotoni, bikongera imikorere myiza cyane.

Imiterere y'Iriba rya Quantum:
Ikoresha urwego ruto cyane rukora kugira ngo ikore ingaruka zo gufunga kwa quantum, inoze imiterere y'umurongo n'umuvuduko w'impinduka.

Izi nyubako zose zagenewe kongera imikorere myiza yo gutera, kongera imvange y’amashanyarazi, no kohereza urumuri mu gace k’aho PN ihurira.

4. Umwanzuro

Urusobe rwa PN ni "umutima" wa laser ya semiconductor. Ubushobozi bwayo bwo gutera ibikoresho munsi y'ubuso bw'imbere ni yo mpamvu y'ingenzi yo gukora laser. Kuva ku gishushanyo mbonera cy'imiterere no guhitamo ibikoresho kugeza ku kugenzura fotoni, imikorere y'igikoresho cyose cya laser ishingira ku kunoza urusobe rwa PN.

Uko ikoranabuhanga rya optoelectronic rikomeza gutera imbere, gusobanukirwa byimbitse fiziki ya PN junction ntibyongera imikorere ya laser gusa ahubwo binashyiraho urufatiro rukomeye rw'iterambere ry'ikinyejana gitaha cya laser za semiconductor zifite imbaraga nyinshi, zihuta cyane kandi zihendutse.