Nchịkọta nke laser pulsed

Nchịkọta nkelasers pulsed

Kacha kpọmkwem ụzọ n'ịwalaserpulses bụ ịgbakwunye modulator n'èzí nke laser na-aga n'ihu. Usoro a nwere ike imepụta pulse picosecond kacha ọsọ ọsọ, ọ bụ ezie na ọ dị mfe, mana ike ọkụ na-ala n'iyi na ike kacha elu enweghị ike ịgafe ike ọkụ na-aga n'ihu. Ya mere, ụzọ dị mma iji mepụta pulses laser bụ imegharị n'ime oghere laser, na-echekwa ike n'oge ụgbọ oloko pulse na-ahapụ ya n'oge. Usoro anọ a na-ejikarị eme ihe n'ịmepụta pulses site na ngbanwe oghere laser bụ ngbanwe uru, ịgbanye Q-ịgbanwe (mgbanwe efu), mkpofu oghere, na mkpọchi ọnọdụ.

Mgbanwe uru na-emepụta mkpirisi mkpirisi site n'ịgbanwe ike mgbapụta. Dị ka ọmụmaatụ, semiconductor uru-switched lasers nwere ike ịmepụta pulses site na ole na ole nanoseconds ruo otu narị picoseconds site ugbu a modulation. Ọ bụ ezie na ike pulse dị ala, usoro a na-agbanwe nke ukwuu, dị ka inye ugboro ugboro ugboro ugboro na obosara usu. N’afọ 2018, ndị ọrụ nyocha na Mahadum Tokyo kọrọ otu laser semiconductor na-enweta uru femtosecond, na-anọchite anya ọganihu n'ime afọ 40 teknụzụ teknụzụ.

A na-emepụta pulses nanosecond siri ike site na lasers Q, bụ nke a na-ebute n'ọtụtụ njem gburugburu n'ime oghere, na ike pulse dị n'ogo nke ọtụtụ millijoules ruo ọtụtụ joules, dabere na nha nke usoro ahụ. Ike ọkara (n'ozuzu n'okpuru 1 μJ) picosecond na femtosecond pulses bụ nke lasers akpọchiri akpọchi na-emekarị. Enwere otu mkpọ ultrashort ma ọ bụ karịa na resonator laser nke na-aga n'ihu. Usu intracavity ọ bụla na-ebufe usu site na enyo njikọ mmepụta, na ugboro ugboro na-adịkarị n'etiti 10 MHz na 100 GHz. Ọnụ ọgụgụ dị n'okpuru na-egosi mgbasasị nkịtị (ANDi) na-agbasa soliton femtoseconderiri laser ngwaọrụ, ọtụtụ n'ime ha nwere ike wuo site na iji Thorlabs ọkọlọtọ components (fiber, lens, mount and displacement table).

Enwere ike iji usoro mkpofu oghereQ-gbanwere lasersiji nweta mkpirisi mkpirisi na lasers ekpochi ọnọdụ iji mee ka ume pulse dịkwuo elu na obere ugboro ugboro.

Ngalaba oge na ngalaba ugboro ugboro
Ọdịdị ahịrị ahịrị nke pulse na oge na-adịkarị mfe ma Gaussian na ọrụ sech² nwere ike igosipụta ya. Oge Pulse (nke a makwaara dị ka obosara usu) na-egosipụtakarị site na uru ọkara-ịdị elu obosara (FWHM), ya bụ, obosara gafee nke ike anya bụ opekata mpe ọkara ike elu; Laser Q-switched na-emepụta nanosecond mkpụmkpụ pulses site na
Laser na-ekpochi ọnọdụ na-emepụta ultra-short pulses (USP) n'usoro nke iri picoseconds ruo femtoseconds. Igwe eletrọnịkị dị elu nwere ike tụọ naanị ihe ruru iri picoseconds, yana mkpirisi mkpirisi ka enwere ike iji naanị teknụzụ ngwa anya dị ka autocorrelator, FROG na SPIDER. Ọ bụ ezie na nanosecond ma ọ bụ ogologo pulses anaghị agbanwe obosara ha ka ha na-eme njem, ọbụlagodi n'ebe dị anya, ihe dị iche iche nwere ike imetụta ọkpụkpụ dị mkpụmkpụ:

Mgbasasa nwere ike ime ka nnukwu pulse gbasaa, mana enwere ike iweghachi ya site na mgbasa ọzọ. Eserese na-esonụ na-egosi ka Thorlabs femtosecond pulse compressor na-akwụ ụgwọ maka mgbasa microscope.

Na-abụghị onlinearity n'ozuzu adịghị emetụta kpọmkwem usu obosara, ma ọ na-agbasawanye bandwit, na-eme ka pulse ọzọ susceptible na mgbasa n'oge mgbasa. Ụdị ọ bụla nke eriri, gụnyere mgbasa ozi ndị ọzọ na-enweta mgbasa ozi nwere oke bandwit, nwere ike imetụta ọdịdị nke bandwit ma ọ bụ ultra-short pulse, na mbelata nke bandwit nwere ike iduga na-amụbawanye na oge; Enwerekwa ebe obosara usu nke usu siri ike na-adị mkpụmkpụ mgbe ụdịdị dị iche iche na-adịwanye warara.