Ubuchwepheshe bomthombo we-laser bokubona i-optical fiber Ingxenye Yesibili

Ubuchwepheshe bomthombo we-laser bokubona i-optical fiber Ingxenye Yesibili

2.2 Ukuskena kwe-wavelength eyodwaumthombo we-laser

Ukuqashelwa kokushelela kwe-laser single wavelength ngokuyinhloko ukulawula izakhiwo zomzimba zedivayisi kui-laseri-cavity (ngokuvamile ubude besikhathi obuphakathi be-bandwidth yokusebenza), ukuze kufezwe ukulawula nokukhetha imodi ye-longitudinal ejikelezayo emgodini, ukuze kufezwe inhloso yokulungisa ubude besikhathi bokuphuma. Ngokusekelwe kulesi simiso, kusukela ngawo-1980, ukuqashelwa kwama-fiber lasers alungisekayo kwafezwa ikakhulukazi ngokufaka esikhundleni sobuso bokugcina obubonisayo be-laser nge-reflective diffraction grating, nokukhetha imodi ye-laser cavity ngokujikeleza ngesandla nangokulungisa i-diffraction grating. Ngo-2011, uZhu nabanye basebenzisa izihlungi ezilungisekayo ukuze kufezwe umphumela we-laser olungisekayo we-single-wavelength one-linewidth encane. Ngo-2016, indlela yokucindezela i-linewidth kaRayleigh yasetshenziswa ekucindezelweni kwe-dual-wavelength, okungukuthi, ukucindezeleka kwasetshenziswa ku-FBG ukuze kufezwe ukulungiswa kwe-laser ye-dual-wavelength, futhi ububanzi be-laser yokukhipha baqashwa ngesikhathi esifanayo, bathola ububanzi bokulungisa ubude besikhathi obungu-3 nm. Umphumela ozinzile we-dual-wavelength one-line width engaba ngu-700 Hz. Ngo-2017, uZhu nabanye. Kusetshenziswe i-graphene kanye ne-micro-nano fiber Bragg grating ukwenza isihlungi esilungisekayo ngokuphelele, futhi kuhlanganiswe nobuchwepheshe bokunciphisa i-laser be-Brillouin, kusetshenziswe umphumela we-photothermal we-graphene eduze kuka-1550 nm ukuze kufezwe ububanzi be-laser obungaphansi kuka-750 Hz kanye nokuskena okusheshayo nokunembile okulawulwa yi-photocontrolled okungu-700 MHz/ms ebangeni le-wavelength elingu-3.67 nm. Njengoba kuboniswe kuMfanekiso 5. Indlela yokulawula i-wavelength engenhla ngokuyisisekelo yenza ukukhetha imodi ye-laser ngokushintsha ngokuqondile noma ngokungaqondile ubude be-wavelength ye-passband yedivayisi emgodini we-laser.

Umfanekiso 5 (a) Ukusethwa kokuhlola kobude be-wavelength obulawulwayo bokukhanyai-laser yefayibha elungisekayokanye nohlelo lokulinganisa;

(b) Ama-spectra okukhiphayo ku-output 2 ngokuthuthukiswa kwephampu yokulawula

2.3 Umthombo wokukhanya we-laser omhlophe

Ukuthuthukiswa komthombo wokukhanya omhlophe kuye kwabhekana nezigaba ezahlukahlukene njengesibani se-halogen tungsten, isibani se-deuterium,i-laser ye-semiconductorkanye nomthombo wokukhanya we-supercontinuum. Ikakhulukazi, umthombo wokukhanya we-supercontinuum, ngaphansi kokukhuthazwa kwama-pulse e-femtosecond noma e-picosecond ngamandla amakhulu esikhashana, ukhiqiza imiphumela engeyona eye-linear yama-oda ahlukahlukene ku-waveguide, futhi i-spectrum inwetshwa kakhulu, engamboza ibhendi kusukela ekukhanyeni okubonakalayo kuya eduze kwe-infrared, futhi inokubambisana okuqinile. Ngaphezu kwalokho, ngokulungisa ukuhlakazeka kanye nokungaqondile kwe-fiber ekhethekile, i-spectrum yayo inganwetshwa ngisho nasebhendini eliphakathi ne-infrared. Lolu hlobo lomthombo we-laser lusetshenziswe kakhulu emikhakheni eminingi, njenge-optical coherence tomography, ukutholwa kwegesi, izithombe zezinto eziphilayo njalonjalo. Ngenxa yokulinganiselwa komthombo wokukhanya kanye ne-nonlinear medium, i-supercontinuum spectrum yokuqala yakhiqizwa kakhulu yi-solid-state laser pumping optical glass ukukhiqiza i-supercontinuum spectrum ebangeni elibonakalayo. Kusukela ngaleso sikhathi, i-optical fiber iye yaba yindlela enhle kakhulu yokukhiqiza i-wideband supercontinuum ngenxa ye-coefficient yayo enkulu engeyona eye-linear kanye nensimu yemodi yokudlulisa encane. Imiphumela eyinhloko engeyona eqondile ifaka phakathi ukuxubana kwamagagasi amane, ukungazinzile kokuguquguquka, ukuguquguquka kwesigaba esizimele, ukuguquguquka kwesigaba esiphambene, ukuhlukaniswa kwe-soliton, ukuhlakazeka kwe-Raman, ukushintshashintsha kwe-soliton self-frequency, njll., futhi isilinganiso somphumela ngamunye sihlukile ngokuya ngobubanzi bokushaya kwe-pulse yokuvuselela kanye nokusabalala kwefayibha. Ngokuvamile, manje umthombo wokukhanya we-supercontinuum uhlose kakhulu ekuthuthukiseni amandla e-laser nokwandisa ububanzi be-spectral, futhi unake ukulawula kwayo ukuhambisana.

3 Isifinyezo

Leli phepha lifingqa futhi libukeze imithombo ye-laser esetshenziselwa ukusekela ubuchwepheshe bokubona i-fiber, okuhlanganisa i-laser encane enobubanzi obuncane, i-laser eyodwa eguquguqukayo kanye ne-laser emhlophe ye-broadband. Izidingo zohlelo lokusebenza kanye nesimo sokuthuthukiswa kwala ma-laser emkhakheni wokubona i-fiber zethulwa ngokuningiliziwe. Ngokuhlaziya izidingo zawo kanye nesimo sokuthuthukiswa, kuphethwa ngokuthi umthombo we-laser ofanele wokubona i-fiber ungafinyelela umphumela we-laser oqinile kakhulu futhi ozinzile kunoma yiliphi ibhendi nanoma yisiphi isikhathi. Ngakho-ke, siqala nge-laser encane enobubanzi obuncane, i-laser encane enobubanzi obuncane kanye ne-laser emhlophe ene-bandwidth enkulu, futhi sithole indlela ephumelelayo yokuthola umthombo we-laser ofanele wokubona i-fiber ngokuhlaziya intuthuko yawo.