Gabatarwa
Hasken tsakiyar-infrared (MIR) a cikin kewayon 2-20 µm yana da amfani don gano sinadarai da ilimin halitta saboda kasancewar yawancin layukan shanyewar kwayoyin halitta a cikin wannan yanki mai ban mamaki.Madaidaicin tushen sake zagayowar, tare da ɗaukar hoto na lokaci ɗaya na kewayon MIR na iya ƙara ba da damar sabbin aikace-aikace kamar mirco-spectroscopy, femtosecond famfo-binciken spectroscopy, da ma'auni mai ƙarfi-tsayi mai ƙarfi Har zuwa yanzu tsare-tsare masu yawa suna da.
an ƙera shi don samar da madaidaicin hasken MIR, kamar layukan katako na synchrotron, lasers cascade na quantum cascade, tushen supercontinuum, oscillators na gani na gani (OPO) da amplifiers na gani parametric (OPA).Waɗannan tsare-tsare duk suna da nasu ƙarfi da raunin nasu dangane da rikitarwa, bandwidth, ƙarfi, inganci, da tsawon lokacin bugun jini.Daga cikin su, haɓakar mitar mitar intra-pulse (IDFG) yana jawo hankalin girma godiya ga haɓakar babban ƙarfin femtosecond 2 µm lasers wanda zai iya yin amfani da ƙananan bandgap maras amfani da lu'ulu'u marasa ƙarfi don samar da babban ƙarfin watsa shirye-shiryen haɗin gwiwar haske na MIR.Idan aka kwatanta da OPOs da OPAs da ake amfani da su na yau da kullun, IDFG yana ba da damar ragewa cikin sarƙaƙƙiyar tsarin da haɓaka aminci, yayin da ake cire buƙatun daidaita katako ko ramuka guda biyu a daidaici mai girma.Bayan haka, fitowar MIR yana da kwanciyar hankali na zamani-envelope-phase (CEP) tare da IDFG.
Hoto 1
Bakan watsawa na 1-mm mai kauri maras rufiBGS crystalDEN TECH ya samar.Wurin shigar yana nuna ainihin kristal da aka yi amfani da shi a wannan gwaji.
Hoto 2
Saitin gwaji na ƙarni na MIR tare da aBGS crystal.OAP, madubi parabolic kashe-axis tare da ingantaccen tsayin daka na 20 mm;HWP, farantin rabi na rabi;TFP, polarizer na bakin ciki;LPF, tace mai tsayi.
A cikin 2010, an ƙirƙira sabon biaxial chalcogenide crystal mara nauyi, BaGa4Se7 (BGSe), ta amfani da hanyar Bridgman-Stockbarger.Yana da kewayon bayyanannu mai faɗi daga 0.47 zuwa 18 µm (kamar yadda aka nuna a siffa 1) tare da ƙididdiga marasa daidaituwa na d11 = 24.3 pm/V da d13 = 20.4 pm/V.Tagar bayyananniyar tagar BGse tana da faɗi sosai fiye da ZGP da LGS duk da cewa rashin kan layi ya yi ƙasa da ZGP (75 ± 8 pm/V).Ya bambanta da GaSe, BGSe kuma za a iya yanke shi a kusurwar da ake so-lokaci kuma yana iya zama mai rufin da ba a taɓa gani ba.
An kwatanta saitin gwaji a cikin siffa 2 (a).An fara samar da bugunan tuƙi daga yanayin gida na Kerr-lens wanda aka kulle Cr: ZnS oscillator tare da polycrystalline Cr: ZnS crystal (5 × 2 × 9 mm3, watsa = 15% a 1908nm) azaman matsakaicin riba wanda aka kunna ta Tm-doped fiber Laser a 1908nm.Juyawa a cikin rami-tsaye yana ba da bugun jini na 45-fs da ke aiki akan ƙimar maimaitawa na 69 MHz tare da matsakaicin ƙarfin 1 W a tsayin dillali na 2.4 µm.Ana ƙara ƙarfin wutar lantarki zuwa 3.3 W a cikin gida-gina-gina-gina guda biyu polycrystalline Cr: ZnS amplifier (5 × 2 × 6 mm3, watsa = 20% a 1908nm da 5 × 2 × 9 mm3, watsa = 15% a 1908nm), kuma ana auna tsawon lokacin bugun bugun fitarwa tare da na'urar da aka gina ta gida ta biyu mai jituwa-tsara-tsarin mitar gani na gani (SHG-FROG).
