Mfundo yogwirira ntchito ya laser ya semiconductor

Mfundo yogwirira ntchito yalaser ya semiconductor

Choyamba, zofunikira za ma parameter a semiconductor lasers zimayambitsidwa, makamaka kuphatikiza zinthu zotsatirazi:
1. Kugwira ntchito kwa Photoelectric: kuphatikiza chiŵerengero cha kutha kwa magetsi, m'lifupi mwake ndi magawo ena, magawo awa amakhudza mwachindunji magwiridwe antchito a ma laser a semiconductor mu machitidwe olumikizirana.
2. Magawo a kapangidwe kake: monga kukula kowala ndi kapangidwe kake, tanthauzo la mapeto a kuchotsa, kukula kwa kukhazikitsa ndi kukula kwa ndondomeko.
3. Kutalika kwa Mafunde: Kutalika kwa mafunde a laser ya semiconductor ndi 650 ~ 1650nm, ndipo kulondola kwake ndi kwakukulu.
4. Mphamvu yamagetsi (Ith) ndi mphamvu yogwirira ntchito (lop): Magawo awa amatsimikizira momwe zinthu zimayambira komanso momwe laser ya semiconductor imagwirira ntchito.
5. Mphamvu ndi magetsi: Poyesa mphamvu, magetsi ndi mphamvu ya laser ya semiconductor yomwe ikugwira ntchito, ma curve a PV, PI ndi IV amatha kukokedwa kuti amvetse mawonekedwe awo ogwirira ntchito.

Mfundo yogwirira ntchito
1. Mikhalidwe Yopezera Mphamvu: Kugawa kwa ma charge carriers mu lasing medium (active region) kumakhazikitsidwa. Mu semiconductor, mphamvu ya ma electron imayimiridwa ndi mndandanda wa mphamvu zomwe zimakhalapo nthawi zonse. Chifukwa chake, chiwerengero cha ma electron pansi pa conduction band mu high energy state chiyenera kukhala chachikulu kwambiri kuposa chiwerengero cha mabowo pamwamba pa valence band mu low energy state pakati pa madera awiri a energy band kuti tikwaniritse inversion ya tinthu. Izi zimachitika pogwiritsa ntchito positive bias ku homojunction kapena heterojunction ndikulowetsa ma carriers ofunikira mu active layer kuti tisangalatse ma electron kuchokera ku lower energy valence band kupita ku high energy conduction band. Pamene ma electron ambiri mu reversed particle population state aphatikizana ndi mabowo, kutulutsa kolimbikitsidwa kumachitika.
2. Kuti mupeze kuwala kogwirizana kolimbikitsidwa, kuwala kolimbikitsidwa kuyenera kubwezeretsedwanso kangapo mu resonator ya optical kuti ipange laser oscillation, resonator ya laser imapangidwa ndi pamwamba pa cleavage yachilengedwe ya crystal ya semiconductor ngati galasi, nthawi zambiri imakutidwa kumapeto kwa kuwala ndi filimu ya dielectric yowunikira kwambiri, ndipo pamwamba pake posalala imakutidwa ndi filimu yowunikira yochepetsedwa. Pa laser ya semiconductor ya Fp cavity (Fabry-Perot cavity), FP cavity imatha kupangidwa mosavuta pogwiritsa ntchito natural cleavage plane perpendicular to the pn junction plane ya crystal.
(3) Kuti pakhale kugwedezeka kokhazikika, chipangizo cha laser chiyenera kukhala ndi mphamvu yokwanira yopezera phindu lokwanira kulipira kutayika kwa kuwala komwe kumachitika chifukwa cha resonator ndi kutayika komwe kumachitika chifukwa cha kutulutsa kwa laser kuchokera pamwamba pa cavity, ndikuwonjezera nthawi zonse kuwala komwe kuli m'kati mwake. Izi ziyenera kukhala ndi jakisoni wamphamvu wamagetsi, ndiko kuti, pali kutembenuka kokwanira kwa tinthu tating'onoting'ono, kuchuluka kwa kutembenuka kwa tinthu tating'onoting'ono, kukwera kwa phindu, ndiko kuti, chofunikira chiyenera kukwaniritsa mkhalidwe winawake wamagetsi. Laser ikafika pamlingo, kuwala kokhala ndi mafunde enaake kumatha kumveka mu cavity ndikukulitsidwa, ndipo pamapeto pake kupanga laser ndi kutulutsa kosalekeza.

Chofunikira pakuchita bwino
1. Kusinthasintha kwa liwiro ndi kuchuluka: ma laser a semiconductor ndi ukadaulo wawo wosinthasintha ndizofunikira kwambiri pakulankhulana kwa kuwala kopanda zingwe, ndipo kuchuluka kwa liwiro ndi kuchuluka kwa liwiro zimakhudza mwachindunji mtundu wa kulumikizana. Laser yosinthidwa mkati (Internal modulated lasers)laser yosinthidwa mwachindunji) ndi yoyenera m'magawo osiyanasiyana a kulumikizana kwa ulusi wa kuwala chifukwa cha kutumiza kwake mwachangu komanso mtengo wake wotsika.
2. Makhalidwe a Spectral ndi mawonekedwe a modulation: Ma laser a feedback ogawidwa ndi semiconductor (Laza ya DFB) akhala gwero lofunika kwambiri la kuwala mu kulumikizana kwa ulusi wa optical ndi kulumikizana kwa kuwala kwa mlengalenga chifukwa cha mawonekedwe awo abwino kwambiri a spectral ndi mawonekedwe awo osinthasintha.
3. Mtengo ndi kupanga zinthu zambiri: Ma laser a semiconductor ayenera kukhala ndi ubwino wa kupanga zinthu zambiri pamtengo wotsika komanso wokwera kuti akwaniritse zosowa za kupanga zinthu zambiri komanso kugwiritsa ntchito zinthu zambiri.
4. Kugwiritsa ntchito mphamvu ndi kudalirika: Mu zochitika monga malo osungira deta, ma laser a semiconductor amafunika kugwiritsa ntchito mphamvu zochepa komanso kudalirika kwambiri kuti atsimikizire kuti ntchitoyo ndi yokhazikika kwa nthawi yayitali.