Taa, anyị ga-ewebata a "monochromatic" laser na oké - warara linewidth laser. Mpụta ya na-ejupụta oghere n'ọtụtụ mpaghara ngwa nke laser, na n'afọ ndị na-adịbeghị anya ejiriwo ya mee ihe n'ọtụtụ ebe na nchọpụta ebili mmiri ike ndọda, liDAR, nkesa nkesa, nkwurịta okwu ngwa anya dị elu na mpaghara ndị ọzọ, nke bụ "ọrụ" nke enweghị ike ịbụ. Emechara naanị site n'ịkwalite ike laser.
Kedu ihe bụ laser linewidth dị warara?
Okwu a bụ "obosara ahịrị" na-ezo aka na obosara ahịrị ahịrị nke laser na mpaghara ugboro ugboro, nke a na-edekarị n'usoro nke ọkara elu zuru oke nke ụdịdị dị iche iche (FWHM). A na-emetụta obosara linen nke ukwuu site na radieshon na-apụtaghị ìhè nke atọm ma ọ bụ ion na-akpali akpali, mkpọtụ oge, ịma jijiji nke igwe resonator, ihe na-ekpo ọkụ na ihe ndị ọzọ dị na mpụga. Obere uru nke obosara ahịrị, nke dị elu nke ịdị ọcha nke ụdịdị dị iche iche, ya bụ, ka mma monochromaticity nke laser. Lasers nwere àgwà ndị dị otú ahụ na-enwekarị obere oge ma ọ bụ ụda ugboro ole na obere mkpọtụ ike ike. N'otu oge ahụ, ntakịrị uru obosara linear nke laser, na-esiwanye ike na nkwekọ kwekọrọ, nke a na-egosipụta dị ka ogologo nkwekọ dị ogologo.
Nghọta na ntinye nke laser linewidth dị warara
Oke site n'inwe uru dị n'obosara nke ihe na-arụ ọrụ nke laser, ọ fọrọ nke nta ka ọ bụrụ ihe na-agaghị ekwe omume ịghọta nsonaazụ nke laser linewidth ozugbo site na ịdabere na oscillator ọdịnala n'onwe ya. Iji ghọta ọrụ nke laser linewidth dị warara, ọ na-adịkarị mkpa iji ihe nzacha, grating na ngwaọrụ ndị ọzọ iji belata ma ọ bụ họrọ modulus ogologo na ụdị uru, na-abawanye uru net dị iche n'etiti ụdị ogologo ogologo, nke mere na enwere ole na ole ma ọ bụ ọbụna naanị otu longitudinal mode oscillation na laser resonator. N'ime usoro a, ọ na-adịkarị mkpa ijikwa mmetụta nke mkpọtụ na mmepụta laser, ma belata mgbasawanye nke ahịrị spectral nke na-eme ka mkpọtụ na mgbanwe okpomọkụ nke gburugburu ebe dịpụrụ adịpụ; N'otu oge ahụ, ọ nwekwara ike jikọta ya na nyocha nke usoro ma ọ bụ ugboro ugboro mkpọtụ spectral density iji ghọta isi iyi nke mkpọtụ na ebuli imewe nke laser, nke mere na iji nweta kwụsiri ike mmepụta nke warara linewidth laser.
Ka anyị leba anya n'ịghọta ọrụ dị warara linewidth nke ọtụtụ ụdị lasers dị iche iche.
Laser semiconductor nwere uru nke nha kọmpat, arụmọrụ dị elu, ogologo ndụ na uru akụ na ụba.
The Fabry-Perot (FP) resonator ngwa anya ejiri na omenalasemiconductor lasersn'ozuzu oscillates na multi-longitudinal mode, na mmepụta ahịrị obosara bụ dịtụ obosara, n'ihi ya, ọ dị mkpa dịkwuo ngwa anya nzaghachi iji nweta mmepụta nke warara ahịrị obosara.
Nzaghachi nke ekesara (DFB) na ntụgharị uche Bragg ekesa (DBR) bụ lasers nyocha nke ime ime n'ime. N'ihi obere grating pitch na ezigbo wavelength selectivity, ọ dị mfe iji nweta mmepụta linewid dị warara kwụsiri ike otu ugboro. Isi ihe dị iche n'etiti ihe owuwu abụọ ahụ bụ ọnọdụ nke grating: ihe owuwu DFB na-ekesa usoro oge nke Bragg grating n'oge resonator, na resonator nke DBR na-abụkarị nke usoro grating echiche na mpaghara uru etinyere n'ime ya. elu njedebe. Na mgbakwunye, lasers DFB na-eji gratings agbakwunyere nwere ọdịiche ntụgharị ntụgharị dị ala yana ntụgharị dị ala. DBR lasers na-eji grating elu elu nwere nnukwu refractive index iche na elu reflectivity. Ihe owuwu abụọ a nwere nnukwu ihe nlegharị anya n'efu ma nwee ike ịrụ nrụgharị ogologo ogologo na-enweghị ịwụli elu n'ogo nke nanometer ole na ole, ebe laser DBR nwere oke nlegharị anya karịaDFB laser. Na mgbakwunye, teknụzụ nzaghachi anya oghere dị n'èzí, nke na-eji ihe ndị na-ahụ anya mpụga na-azaghachi ọkụ na-apụ apụ nke mgbawa laser semiconductor wee họrọ ugboro ole, nwekwara ike ghọta ọrụ eriri nke semiconductor laser.
(2) Fiber lasers
Fiber lasers nwere elu mgbapụta ngbanwe arụmọrụ, ezigbo ọkụ ọkụ na arụmọrụ dị elu, nke bụ isiokwu nyocha na-ekpo ọkụ na mpaghara laser. Na onodu nke ozi afọ, fiber lasers nwere ezi ndakọrịta na ugbu a ngwa anya fiber nkwurịta okwu usoro na ahịa. The otu-ugboro fiber laser na uru nke warara ahịrị obosara, ala mkpọtụ na ezi coherence aghọwo otu n'ime mkpa ntụziaka nke ya mmepe.
Single longitudinal mode ọrụ bụ isi nke eriri laser nweta warara akara-obosara mmepụta, na-emekarị dị ka Ọdịdị nke resonator nke otu ugboro eriri laser nwere ike kewara n'ime DFB ụdị, DBR ụdị na mgbanaka ụdị. N'ime ha, ụkpụrụ ọrụ nke DFB na DBR otu ugboro fiber lasers yiri nke DFB na DBR semiconductor lasers.
Dị ka egosiri na eserese 1, laser fiber DFB ga-ede ihe na-ekesa Bragg grating n'ime eriri. N'ihi na ogologo oge na-arụ ọrụ nke oscillator na-emetụta oge eriri, enwere ike ịhọrọ ọnọdụ ogologo oge site na nzaghachi kesara nke grating. A na-emepụta laser resonator nke DBR laser site na ụzọ abụọ fiber Bragg gratings, na otu longitudinal mode na-ahọrọ nke ọma site na warara band na obere reflectivity fiber Bragg gratings. Otú ọ dị, n'ihi na nke ogologo resonator, mgbagwoju Ọdịdị na enweghị irè ugboro ịkpa ókè usoro, mgbanaka ekara oghere na-adịkarị mfe mode hopping, na ọ na-esi ike na-arụ ọrụ stably na-adịgide adịgide longitudinal mode ruo ogologo oge.
Ọgụgụ 1, Ọdịdị ahịrị abụọ na-ahụkarị nke otu ugboroeriri lasers
Oge nzipu: Nov-27-2023