Nkọwa nke laser pulsed

Nchịkọta nkelaser pulsed

Ụzọ kachasị kpọmkwem iji mepụtalaserpulses bụ itinye modulator na mpụga nke laser na-aga n'ihu. Usoro a nwere ike imepụta picosecond pulse kachasị ọsọ, ọ bụ ezie na ọ dị mfe, mana ike ọkụ efu na ike kachasị elu enweghị ike ịgafe ike ọkụ na-aga n'ihu. Ya mere, ụzọ kachasị dị irè iji mepụta pulses laser bụ ịgbanwee n'ime oghere laser, ịchekwa ike n'oge na-adịghị anya nke ụgbọ okporo ígwè pulse ma hapụ ya n'oge. Usoro anọ a na-ejikarị emepụta pulses site na modulation oghere laser bụ uru mgbanwe, Q-switching (mgbanwe efu), oghere efu, na mode-locking.

Mgbanwe uru na-emepụta mkpụmkpụ mkpali site na ịgbanwe ike mgbapụta. Dịka ọmụmaatụ, lasers gain-switched semiconductor nwere ike ịmepụta mkpali site na nanoseconds ole na ole ruo narị picoseconds site na modulation ugbu a. Ọ bụ ezie na ike pulse dị ala, usoro a na-agbanwe agbanwe nke ukwuu, dịka inye ugboro ugboro a na-agbanwe agbanwe na obosara pulse. Na 2018, ndị nchọpụta na Mahadum Tokyo kọrọ na femtosecond gain-switched semiconductor laser, nke na-anọchite anya ọganihu na nsogbu teknụzụ afọ 40.

A na-emepụta pulse nanosecond siri ike site na laser Q-switched, nke a na-ewepụta n'ọtụtụ njem gburugburu n'ime oghere ahụ, ike pulse dịkwa n'ọtụtụ millijoules ruo ọtụtụ joules, dabere na nha sistemụ ahụ. Ike dị n'etiti (n'ozuzu ya dị n'okpuru 1 μJ) picosecond na femtosecond pulses bụ isi site na lasers ndị nwere mode-locked. Enwere otu ma ọ bụ karịa ultrashort pulses na laser resonator nke na-agagharị mgbe niile. Mkpụrụ obi intracavity ọ bụla na-ebufe pulse site na enyo njikọ mmepụta, refrequency na-abụkarị n'etiti 10 MHz na 100 GHz. Foto dị n'okpuru na-egosi dispersion nkịtị (ANDi) dissipative soliton femtosecondngwaọrụ eriri laser, enwere ike iji ihe ndị Thorlabs ji arụ ọrụ (eriri, lensị, ihe ndị dị n'elu na tebụl ndị na-agbanwe agbanwe) rụọ ọtụtụ n'ime ha.

Enwere ike iji usoro iwepụ oghere makaLaser ndị a na-akpọ Q-switchediji nweta mkpụmkpụ mkpali na laser ndị e ji ụdị mkpọchi mee iji mee ka ike mkpali dịkwuo elu na obere ugboro ugboro.

Mgbasa ozi ngalaba oge na ugboro ugboro
Ọdịdị ahịrị nke pulse na oge na-adịkarị mfe ma enwere ike igosipụta ya site na ọrụ Gaussian na sech². A na-egosipụtakarị oge pulse (a makwaara dị ka obosara pulse) site na uru ọkara-elu (FWHM), ya bụ, obosara nke ike anya dị ma ọ dịkarịa ala ọkara ike kacha elu; laser Q-switched na-emepụta obere pulses nanosecond site na
Laser ndị a na-akpọchi ụdịdị na-emepụta pulses dị mkpụmkpụ (USP) n'usoro nke iri picoseconds ruo femtoseconds. Ngwaọrụ eletrọniki dị elu nwere ike iru naanị iri picoseconds, a pụkwara ịtụ pulses dị mkpụmkpụ naanị site na iji teknụzụ anya dị ka autocorrelators, FROG na SPIDER. Ọ bụ ezie na nanosecond ma ọ bụ pulses dị ogologo anaghị agbanwe obosara pulse ha ka ha na-eme njem, ọbụlagodi n'ebe dị anya, ọtụtụ ihe nwere ike imetụta pulses dị mkpụmkpụ:

Mgbasa nwere ike ime ka nnukwu pulse gbasaa, mana enwere ike iji mgbasa dị iche mee ihe ọzọ. Ihe osise a na-egosi otu Thorlabs femtosecond pulse compressor si emezi maka mgbasa microscope.

Enweghị akara anaghị emetụta obosara pulse ozugbo, kama ọ na-eme ka bandwit ahụ gbasaa, na-eme ka pulse ahụ dịkwuo mfe ịgbasa n'oge mgbasa. Ụdị eriri ọ bụla, gụnyere ihe ndị ọzọ na-enweta uru nwere obere bandwit, nwere ike imetụta ọdịdị nke bandwit ma ọ bụ ultra-short pulse, mbelata na bandwit nwekwara ike ibute mmụba n'oge; E nwekwara ọnọdụ ebe obosara pulse nke pulse siri ike na-adị mkpụmkpụ mgbe spectrum na-adị obere.