Yintoni i-laser cryogenic

Ingcamango ye-lasers esebenza kumaqondo okushisa aphantsi ayiyinto entsha: i-laser yesibini kwimbali yayiyi-cryogenic. Ekuqaleni, le ngcamango yayinzima ukufezekisa ukusebenza kweqondo lokushisa kwegumbi, kwaye intshiseko yomsebenzi weqondo eliphantsi lobushushu laqala ngo-1990 kunye nokuphuhliswa kweelaser ezinamandla kunye ne-amplifiers.

Ngamandla aphezuluimithombo laser, iziphumo ezishushu ezifana nokulahleka kwe-depolarization, i-lens ye-thermal okanye i-laser crystal ukugoba kunokuchaphazela ukusebenzaumthombo wokukhanya. Ngokupholisa ubushushu obuphantsi, uninzi lweziphumo eziyingozi zobushushu zinokucinezelwa ngokusebenzayo, oko kukuthi, indawo yokuzuza ifuna ukupholiswa ukuya kwi-77K okanye nakwi-4K. Isiphumo sokupholisa ikakhulu sibandakanya:

I-conductivity yeempawu ze- gain medium inhibited kakhulu, ikakhulu ngenxa yokuba intsingiselo yendlela yamahhala yentambo iyanda. Ngenxa yoko, iqondo lokushisa liyehla kakhulu. Ngokomzekelo, xa iqondo lokushisa liyancipha ukusuka kwi-300K ukuya kwi-77K, i-thermal conductivity ye-crystal ye-YAG iyanda nge-factor of seven.

I-coefficient ye-thermal diffusion nayo iyancipha ngokukhawuleza. Oku, kunye nokunciphisa i-gradient yeqondo lokushisa, kubangela ukuthotywa kwe-thermal lensing effect kwaye ngoko ke ukuncitshiswa kokunciphisa uxinzelelo.

I-coefficient ye-thermo-optical nayo iyancitshiswa, iyancipha ngakumbi i-lens ye-thermal effect.

Ukonyuka kwecandelo lomnqamlezo we-ion yomhlaba enqabileyo kubangelwe ikakhulu kukuncipha kokwandisa okubangelwa yimpembelelo yobushushu. Ke ngoko, amandla okugcwalisa ayancipha kwaye inzuzo ye-laser iyanda. Ngoko ke, amandla ompompo embundwini ancitshisiwe, kwaye i-pulses emfutshane inokufumaneka xa ukutshintshwa kwe-Q kusebenza. Ngokwandisa ukuhanjiswa kwe-coupler ye-output, ukusebenza kakuhle kwethambeka kunokuphuculwa, ngoko ke umphumo welahleko we-parasitic uyancipha.

Inani leenxalenye zenqanaba eliphantsi eliphantsi kwinqanaba le-quasi-ezintathu-level gain medium liyancitshiswa, ngoko ke umbane wokupompa umqobo uyancitshiswa kwaye umbane ophuculweyo uphuculwe. Ngokomzekelo, i-Yb: YAG, evelisa ukukhanya kwi-1030nm, inokubonwa njengenkqubo yenqanaba le-quasi-three-level kwiqondo lokushisa, kodwa inkqubo yemigangatho emine kwi-77K. Er: Kunjalo nakwi YAG.

Ngokuxhomekeke kwindlela yokuzuza, ukuqina kweenkqubo ezithile zokucima kuya kuncitshiswa.

Ngokudityaniswa nezinto ezingentla, ukusebenza kweqondo lokushisa eliphantsi kunokuphucula kakhulu ukusebenza kwelaser. Ngokukodwa, iilaser zokupholisa ubushushu obuphantsi zinokufumana amandla aphezulu kakhulu ngaphandle kwefuthe lobushushu, oko kukuthi, umgangatho olungileyo unokufumaneka.

Umba omnye ekufuneka uqwalaselwe kukuba kwikristale ye-laser cryocooled, i-bandwidth yokukhanya okusasazeka kunye nokukhanya okufunliweyo kuya kuncitshiswa, ngoko ke uluhlu lwe-wavelength tuning luya kuba luncinci, kwaye ububanzi bomgca kunye nokuzinza kwe-wavelength ye-laser pumped kuya kuba nzima ngakumbi. . Nangona kunjalo, le mpembelelo idla ngokungaqhelekanga.

Ukupholisa kweCryogenic ngokuqhelekileyo kusebenzisa isipholile, esifana nenitrogen engamanzi okanye i-helium engamanzi, kwaye ngokufanelekileyo isikhenkcisi sijikeleza ngetyhubhu encanyathiselwe kwikristale yelaser. Ukupholisa kuzaliswa kwakhona kwangexesha okanye kusetyenziswe kwakhona kwiluphu evaliweyo. Ukuze ugweme ukuqina, ngokuqhelekileyo kuyimfuneko ukubeka i-laser crystal kwigumbi lokucoca.

Ingqikelelo yeekristale ze-laser ezisebenza kumaqondo obushushu aphantsi angasetyenziswa nakwi-amplifiers. I-Titanium sapphire ingasetyenziselwa ukwenza i-amplifier yempendulo encomekayo, i-avareji yemveliso yamandla kumashumi e-watts.

Nangona izixhobo zokupholisa i-cryogenic zinokuba nzimaiinkqubo laser, iinkqubo zokupholisa eziqhelekileyo zihlala zilula kakhulu, kwaye ukusebenza kakuhle kokupholisa i-cryogenic kuvumela ukucutha okuthile kobunzima.