Ukubuka konke kwama-laser ashukunyiswayo

Ukubuka konke kweama-laser ashukunyiswayo

Indlela eqondile kakhulu yokukhiqizai-laserAma-pulse angokwengeza i-modulator ngaphandle kwe-laser eqhubekayo. Le ndlela ingakhiqiza i-picosecond pulse esheshayo, nakuba ilula, kodwa amandla okukhanya alahlekile kanye namandla aphezulu awakwazi ukudlula amandla okukhanya okuqhubekayo. Ngakho-ke, indlela ephumelela kakhulu yokukhiqiza ama-laser pulse iwukuguqula i-laser cavity, ukugcina amandla ngesikhathi sokungasebenzi kwe-pulse train bese uyikhulula ngesikhathi. Amasu amane avamile asetshenziswa ukukhiqiza ama-pulse ngokusebenzisa i-laser cavity modulation ukushintshwa kwe-gain, i-Q-switching (ukushintsha kokulahlekelwa), ukukhipha i-cavity, kanye ne-mode-locking.

I-gain switch ikhiqiza ama-pulse amafushane ngokushintsha amandla ephampu. Isibonelo, ama-laser e-semiconductor gain-switched angakhiqiza ama-pulse kusukela kuma-nanosecond ambalwa kuya kuma-picosecond ayikhulu ngokushintshashintsha kwamanje. Nakuba amandla e-pulse ephansi, le ndlela iguquguquka kakhulu, njengokunikeza imvamisa yokuphindaphinda elungisekayo kanye nobubanzi be-pulse. Ngo-2018, abacwaningi eNyuvesi yaseTokyo babike nge-femtosecond gain-switched semiconductor laser, emele intuthuko emgodleni wobuchwepheshe weminyaka engama-40.

Ama-pulse e-nanosecond aqinile ngokuvamile akhiqizwa ama-laser e-Q-switched, akhishwa ngezikhathi eziningana ezijikelezayo emgodini, futhi amandla e-pulse aphakathi kwama-millijoule amaningana kuya kuma-joule amaningana, kuye ngobukhulu besistimu. Ama-pulse e-picosecond kanye ne-femtosecond akhiqizwa kakhulu ama-laser avaliwe ngemodi. Kukhona ama-pulse amafushane owodwa noma ngaphezulu ku-resonator ye-laser ajikeleza njalo. I-pulse ngayinye ye-intracavity idlulisela i-pulse ngesibuko sokuxhuma esiphumayo, futhi i-refrequency ngokuvamile iphakathi kwe-10 MHz ne-100 GHz. Isithombe esingezansi sibonisa i-dispersion evamile (ANDi) dissipative soliton femtosecond.idivayisi ye-fiber laser, iningi lazo lingakhiwa kusetshenziswa izingxenye ezijwayelekile ze-Thorlabs (i-fiber, ilensi, i-mount kanye netafula lokufuduka).

Indlela yokukhipha imigodi ingasetshenziswaAma-laser ashintshiwe nge-Qukuthola ama-pulse amafushane kanye nama-laser avaliwe ngemodi ukuze kwandiswe amandla e-pulse ngokuphindaphinda okuphansi.

Ama-pulse esizinda sesikhathi kanye nesizinda semvamisa
Ukuma okuqondile kwe-pulse ngesikhathi ngokuvamile kulula kakhulu futhi kungabonakaliswa ngemisebenzi ye-Gaussian kanye ne-sech². Isikhathi se-pulse (esaziwa nangokuthi ububanzi be-pulse) sivame ukuvezwa yinani le-half-height width (FWHM), okungukuthi, ububanzi lapho amandla okukhanya angaphezulu kwesigamu samandla aphezulu; i-laser ye-Q-switched ikhiqiza ama-nanosecond short pulses ngokusebenzisa
Ama-laser avaliwe ngemodi akhiqiza ama-pulse amafushane kakhulu (i-USP) ngokulandelana kwamashumi ama-picosecond kuya kuma-femtosecond. Ama-elekthronikhi ashesha kakhulu angalinganisa amashumi ama-picosecond kuphela, kanti ama-pulse amafushane angalinganiswa kuphela ngobuchwepheshe bokukhanya obufana nama-autocorrelators, i-FROG kanye ne-SPIDER. Nakuba ama-pulse e-nanosecond noma amade engashintshi ububanzi bawo be-pulse njengoba ehamba, ngisho nasebangeni elide, ama-pulse amafushane kakhulu angathinteka yizici ezahlukahlukene:

Ukuhlakazeka kungabangela ukwanda kwe-pulse enkulu, kodwa kungacindezelwa kabusha ngokuhlakazeka okuphambene. Umdwebo olandelayo ubonisa indlela i-Thorlabs femtosecond pulse compressor ekhokhela ngayo ukuhlakazeka kwe-microscope.

Ukungalungi kahle ngokuvamile akuthinti ngqo ububanzi be-pulse, kodwa kwandisa i-bandwidth, okwenza i-pulse ibe sengozini yokusabalala ngesikhathi sokusabalala. Noma yiluphi uhlobo lwe-fiber, okuhlanganisa nezinye i-gain media ezine-bandwidth elinganiselwe, lungathinta ukuma kwe-bandwidth noma i-pulse emfushane kakhulu, futhi ukwehla kwe-bandwidth kungaholela ekwandeni kwesikhathi; Kukhona futhi izimo lapho ububanzi be-pulse ye-pulse ephithizelayo kakhulu buba bufushane lapho i-spectrum iba ncane.