Menene laser cryogenic

Manufar lasers da ke aiki a ƙananan yanayin zafi ba sabon abu ba ne: Laser na biyu a tarihi shine cryogenic. Da farko, ra'ayin yana da wuya a cimma aikin zafin jiki, kuma sha'awar aikin ƙananan zafin jiki ya fara a cikin 1990s tare da haɓaka manyan lasers da amplifiers.

A cikin babban ikotushen laser, thermal effects kamar depolarization hasãra, thermal ruwan tabarau ko Laser crystal lankwasawa na iya shafar aikin natushen haske. Ta hanyar sanyi mai ƙarancin zafi, yawancin tasirin thermal masu cutarwa za a iya danne su yadda ya kamata, wato, matsakaicin riba yana buƙatar sanyaya zuwa 77K ko ma 4K. Tasirin sanyaya musamman ya haɗa da:

Halayen halayen matsakaicin riba an hana su sosai, galibi saboda ma'anar hanyar igiya ta kyauta. A sakamakon haka, yanayin zafin jiki yana raguwa sosai. Misali, lokacin da aka saukar da zafin jiki daga 300K zuwa 77K, yanayin zafin jiki na YAG crystal yana ƙaruwa da kashi bakwai.

Ƙimar watsawar thermal kuma tana raguwa sosai. Wannan, tare da raguwa a cikin yanayin zafin jiki, yana haifar da raguwar tasirin ruwan tabarau na thermal don haka rage yiwuwar fashewar damuwa.

Hakanan an rage ma'aunin ma'aunin zafin jiki, yana ƙara rage tasirin ruwan tabarau na thermal.

Haɓaka ɓangaren ƙetare na ion ƙasa mai wuya ya samo asali ne saboda raguwar faɗaɗawa sakamakon tasirin zafi. Sabili da haka, ana rage ƙarfin jikewa kuma ana ƙara samun riba. Sabili da haka, ƙarfin famfo na bakin kofa yana raguwa, kuma ana iya samun guntun bugun jini lokacin da maɓallin Q yana aiki. Ta hanyar haɓaka isar da ma'aunin fitarwa, ana iya inganta haɓakar gangara, don haka tasirin asarar kogon parasitic ya zama ƙasa da mahimmanci.

Adadin barbashi na jimlar ƙananan matakin matsakaicin matsakaici-mataki uku ya ragu, don haka ana rage ikon yin famfo kofa kuma ana inganta ƙarfin wutar lantarki. Misali, Yb: YAG, wanda ke samar da haske a 1030nm, ana iya ganin shi a matsayin tsarin ma'auni-uku a yanayin zafi, amma tsarin matakai hudu a 77K. Er: Haka yake ga YAG.

Dangane da matsakaicin riba, za a rage ƙarfin wasu matakan kashewa.

Haɗe tare da abubuwan da ke sama, ƙananan aiki na zafin jiki na iya inganta aikin laser sosai. Musamman ma, ƙananan laser na sanyaya zafin jiki na iya samun ƙarfin fitarwa sosai ba tare da tasirin thermal ba, wato, ana iya samun ingancin katako mai kyau.

Ɗaya daga cikin batu da za a yi la'akari da shi shine cewa a cikin kristal laser cryocooled, za a rage girman bandwidth na hasken da ke haskakawa da kuma hasken da aka ɗauka, don haka tsayin tsayin tsayin daka zai zama kunkuntar, kuma fadin layin da tsayin daka na laser famfo zai zama mafi stringent. . Duk da haka, wannan tasirin yana da wuyar gaske.

Cryogenic sanyaya yawanci yana amfani da mai sanyaya, kamar ruwa nitrogen ko helium ruwa, kuma da kyau refrigerant yana yawo ta cikin bututun da aka makala zuwa crystal crystal. Ana sake cika sanyi cikin lokaci ko kuma ana sake yin fa'ida a cikin rufaffiyar madauki. Don guje wa ƙarfafawa, yawanci ya zama dole a sanya kristal laser a cikin ɗakin da ba a so.

Hakanan ana iya amfani da ma'anar lu'ulu'u na Laser da ke aiki a ƙananan zafin jiki zuwa amplifiers. Titanium sapphire za a iya amfani da shi don yin ingantacciyar amsa amplifier, matsakaicin ƙarfin fitarwa a cikin dubun watts.

Ko da yake na'urorin sanyaya na cryogenic na iya rikitarwatsarin laser, Mafi yawan tsarin sanyi na yau da kullum sau da yawa sau da yawa ba su da sauƙi, kuma yadda ya dace na kwantar da hankali na cryogenic yana ba da damar rage yawan rikitarwa.