简介：宽波段红外成像技术可以获取丰富的波段信息,在目标识别和频谱分析中具有独特的优势。设计了一种1.3-5μm宽波段短中波红外光学系统,该光学系统采用二次成像设计,包括7块透镜和2片反射镜,其中使用了2片硅非球面和1片硒化锌基底衍射面用以校正像差和色差。利用光学设计软件给出了系统的光学参数和二维外形结构图,并且对其像质和冷反射进行了系统分析。该系统可以实现在工作波段1.3-5μm宽波段中成像,其F数为2,满足100%冷光阑效率。该系统结构紧凑,像质较好,能够实现宽波段成像要求。

简介：Athree-dimensionalmodelofGaAs/A1GaAsquantumdoubleringsinthelateralstaticelectricfieldisinvestigatedtheoretically.Theeigenvalueproblemwiththeeffective-massapproximationissolvedbymeansofthefinite-elementmethod.Theenergylevelsandwavefunctionsofquantum-confinedelectronsandheavyholesareobtainedandshowanagreementwithourprevioustheoreticalandexperimentalstudies.ItisshownintheapproximationofneglectingtheCoulombattractionbetweentheelectronandheavyholethatarelativelylargeStarkshiftofexcitonemissionof4meVisattainablewithanappliedelectricfieldof0.7kV/cm.

简介：Morethan6Waveragepowerultravioletradiationat355nmwasgeneratedinLiB3O5(LBO)crystalthroughthefrequencymixingofthefundamentalandsecondharmonicradiationofaNd:YAGlaser.Thisperformancewasachievedwith38%optical-to-opticalconversionefficiency(532nmto355nm).

简介：WecreateaGaNphotocathodebasedongradedAlxGa1-xNbufferlayerstoovercometheinfluenceofbuffer-emissionlayerinterfaceonthephotoemissionoftransmission-modeGaNphotocathodes.Agateshapedspectralresponsewitha260-nmstartingwavelengthanda375-nmcut-offwavelengthisobtained.Averagequantumefficiencyis15%andshortwavelengthresponsesarealmostequivalenttolongwavelengthones.Thefittedinterfacerecombinationvelocityis5×104cm/s,withnegligiblemagnitude,provingthatthedesignofthegradedbufferlayersisefficientinobtaininggoodinterfacequalitybetweenthebufferandtheemissionlayer.

简介：Asecondgenerationsolaradaptiveoptics(AO)systemisbuiltandinstalledatthe1-mNewVacuumSolarTelescope(NVST)oftheFuxianSolarObservatory(FSO)in2015.TheAOhigh-ordercorrectionsystemconsistsofa151-elementdeformablemirror(DM),acorrelatingShack–Hartmann(SH)wavefrontsensor(WFS)witha3500Hzframerate,andareal-timecontroller.ThesystemsawfirstlightonMar.16,2015.Thesimultaneoushigh-resolutionphotosphereandchromosphereimageswithAOareobtained.Theon-skyobservationalresultsshowthatthecontrastandresolutionoftheimagesareapparentlyimprovedafterthewavefrontcorrectionbyAO.

简介：Wereportonthecontinuous-wave（CW）andpassiveQ-switchingperformanceofaminiatureYb:Y3Ga5O12crystallaserendpumpedbya935-nmdiodelaser.AmaximumCWoutputpowerof12.03Wisproducedwithanoptical-to-opticalefficiencyof54.4%,whiletheslopeefficiencyis63%.InthepassivelyQ-switchedoperationachievedwithaCr4+:YAGsaturableabsorber,anaverageoutputpowerof2.12Wat1025.2nmisgeneratedwithaslopeefficiencyof46%atapulserepetitionrateof5.0kHz.Thepulse’senergy,duration,andpeakpowerare424μJ,2.3ns,and184.3kW,respectively.

简介：Anall-fiberopticallaserpulsemulti-passstretcherusingachirpedfiberBragggrating(CFBG)isdemonstrated.Pulsesfroma1053-nmmode-lockedfiberseedoscillatorarestretchedbymultiplepassingthroughachirpedfibergratingsetinafiberregenerativeamplifierstructure.Westretchthepulsefrom16psto1.855nsafterittransmitssevenloopsinthestretcher.Themainfactorsthataffectthestretchingresultsarediscussed.

简介：SiO_2thinfilmscontainingSi_(1-x)Ge_xquantumdots(QDs)arepreparedbyionimplantationandannealingtreatment.Thephotoluminescence(PL)andmicrostructuralpropertiesofthinfilmsareinvestigated.ThesamplesexhibitstrongPLinthewavelengthrangeof400—470nmandrelativelyweakPLpeaksat730and780nmatroomtemperature.Blueshiftisfoundforthe400-nmPLpeak,andtheintensityincreasesinitiallyandthendecreaseswiththeincreaseofGe-dopingdose.Weproposethatthe400—470nmPLbandoriginatesfrommultipleluminescencecenters,andthe730-and780-nmPLpeaksareascribedtotheSi=OandGeOluminescencecenters.

简介：Adiode-end-pumpedelectro-optic(EO)Q-switchedNd:YVO4laseroperatingatrepetitionrateof10kpps(pulsespersecond)wasreported.AblockofLa3Ga5SiO14(LGS)singlecrystalwasusedasaQ-switchandthedriverwasametaloxidesemiconductorfieldeffecttransistor(MOS-FET)pulserofhighrepetitionrateandhighvoltage.Atcontinuouswave(CW)operation,theslopeefficiencyofthelaserwas46%,andmaximumoptical-to-opticalefficiencywas38.5%.Usinganoutputcouplerwithtransmissionof70%,a10-kppsQ-switchedpulsetrainwith0.4-mJmonopulseenergyand8.2-nspulsewidthwasachieved,theopticalconversionefficiencywasaround15%,andthebeamqualityM2factorwaslessthan1.2.