Pfupiso ye pulsed lasers

Pfupiso yemalaser ane pulsed

Nzira yakananga kwazvo yekugadziralaserpulses ndeyekuwedzera modulator kunze kwe continuous laser. Nzira iyi inogona kugadzira picosecond pulse inokurumidza, kunyangwe iri nyore, asi simba rechiedza rinorasika uye simba repamusoro hazvigone kudarika simba rechiedza rinoenderera mberi. Nokudaro, nzira inoshanda zvikuru yekugadzira laser pulses ndeyekuchinja mu laser cavity, kuchengetedza simba panguva yekushanda kwe pulse train uye kuriburitsa panguva. Nzira ina dzakajairika dzinoshandiswa kugadzira pulses kuburikidza ne laser cavity modulation ndedze gain switching, Q-switching (loss switching), cavity emptying, uye mode-locking.

Shanduko ye gain inogadzira ma pulse mapfupi nekuchinja simba repombi. Semuenzaniso, ma semiconductor gain-switched lasers anogona kugadzira ma pulse kubva kuma nanoseconds mashoma kusvika kuma picoseconds zana ne current modulation. Kunyangwe simba re pulse riri shoma, nzira iyi inochinjika zvikuru, senge kupa adjustable repetition frequency uye pulse width. Muna 2018, vaongorori vepaYunivhesiti yeTokyo vakashuma femtosecond gain-switched semiconductor laser, ichimiririra budiriro mudambudziko rehunyanzvi remakore makumi mana.

Mapurose e nanosecond akasimba anowanzo gadzirwa nema-laser eQ-switched, ayo anoburitswa mumatanho akati wandei mugomba, uye simba repulse riri pakati pemamilijoules akati wandei kusvika kumajoules akati wandei, zvichienderana nehukuru hwesystem. Simba repakati (kazhinji riri pasi pe1 μJ) mapurosese epicosecond nefemtosecond anonyanya kugadzirwa nema-laser emode-locked. Kune rimwe kana kupfuura mapurosese eultrashort mulaser resonator anotenderera nguva dzose. Pulse yega yega yemukati memusuwo inotumira pulse kuburikidza negirazi rekubatanidza rinobuda, uye refrequency inowanzo kuve pakati pe10 MHz ne100 GHz. Mufananidzo uri pazasi unoratidza dispersion yakajairika (ANDi) dissipative soliton femtosecond.mudziyo wefiber laser, iyo yakawanda inogona kuvakwa uchishandisa zvikamu zveThorlabs (fiber, lens, mount uye displacement table).

Nzira yekuburitsa maburi inogona kushandiswaMalaser eQ-switchedkuwana mapulse mapfupi uye ma lasers akavharirwa mode kuti uwedzere simba repulse nekudzokorora kwakaderera.

Kufamba kwenzvimbo yenguva uye mafrequency enzvimbo
Chimiro chemutsara chepulse nenguva chinowanzo kuve nyore uye chinogona kuratidzwa nemabasa eGaussian nesech². Nguva yepulse (inozivikanwawo sehupamhi hwepulse) inowanzoratidzwa nehupamhi hwehafu-hurefu (FWHM), kureva kuti, upamhi hwayo simba re optical riri hafu yesimba repamusoro; laser yeQ-switched inogadzira nanosecond short pulses kuburikidza
MaLaser ane Mode-locked anogadzira ma pulse mapfupi (USP) muchikamu chemakumi ema picoseconds kusvika kuma femtoseconds. Ma electronics ane kumhanya kwepamusoro anogona kuyera makumi ema picoseconds chete, uye ma pulse mapfupi anogona kuyera chete ne matekinoroji e optical akadai se autocorrelators, FROG ne SPIDER. Kunyange zvazvo ma nanosecond kana ma pulse marefu asingachinji upamhi hwe pulse yawo paanenge achifamba, kunyangwe padaro refu, ma pulse mapfupi anogona kukanganiswa nezvinhu zvakasiyana-siyana:

Kupararira kunogona kukonzera kupararira kukuru kwemwoyo, asi kunogona kudzvinyirirwa zvakare nekupararira kwakasiyana. Dhayagiramu inotevera inoratidza kuti Thorlabs femtosecond pulse compressor inotsiva sei kupararira kwemakroskopu.

Kusawirirana kazhinji hakukanganisi zvakananga upamhi hwepulse, asi kunowedzera bandwidth, zvichiita kuti pulse ive nyore kupararira panguva yekupararira. Chero rudzi rwefiber, kusanganisira mamwe ma gain media ane bandwidth shoma, inogona kukanganisa chimiro chebandwidth kana ultra-short pulse, uye kudzikira kwebandwidth kunogona kutungamira mukuwedzera kwenguva; Kunewo zviitiko apo upamhi hwepulse hwepulse ine chirped yakasimba hunova hupfupi kana spectrum ikava diki.