飞秒激光脉冲测量方案.ppt

飞秒脉冲的测量方案 Measurementofanultrashortpulse Outlines 为什么测量超短脉冲是一项挑战 为什么要对超短脉冲进行测量 对超短脉冲的全面描述需要那些测量量 光谱仪与Michelson干涉仪自相关法频率分辨光学开关法 FROG 光谱相位干涉直接电场重构法 SPIDER 超短脉冲的测量 自相关法 Outlines IntensityAutocorrelationSingle shotautocorrelationThird orderAutocorrelationIntensityCross CorrelationInterferometricAutocorrelation 强度自相关器 CrossingbeamsinanSHGcrystal varyingthedelaybetweenthem andmeasuringthesecond harmonic SH pulseenergyvs delayyieldstheIntensityAutocorrelation TheIntensityAutocorrelation Delay Beam splitter Inputpulse ApertureeliminatesinputpulsesandalsoanySHcreatedbytheindividualinputbeams Slowdetector Mirror E t E t t Mirrors SHGcrystal Lens Whatifweuseacollinearbeamgeometry andallowtheautocorrelatorsignallighttointerferewiththeSHGfromeachindividualbeam DevelopedbyJ CDiels Alsocalledthe Fringe ResolvedAutocorrelation Filter Slowdetector SHGcrystal Lens Beam splitter Inputpulse Delay Mirror Mirror E t E t t MichelsonInterferometer DielsandRudolph UltrashortLaserPulsePhenomena AcademicPress 1996 干涉自相关器 Outlines TheMusicalScoreandtheSpectrogramFrequency ResolvedOpticalGating FROG SHG FROGandothergeometriesXFROG Single shotFROGandGRENOILLE 超短脉冲测量 频率分辨光开关法 FROG 用复制的可延迟的脉冲与原脉冲在非线性介质中的瞬时相互作用作为光学开关 对开关脉冲随时间的变化进行光谱分辨 Useanyultrafastnonlinearity Second harmonicgeneration etc 频率分辨光学开关法 FROG Baltuska Pshenichnikov andWeirsma J Quant Electron 35 459 1999 SHGFROGMeasurementsofa4 5 fsPulse 超短脉冲测量 SPIDER WhatisSPIDER HowSPIDERworks SPIDERapparatusX SPIDER Outlines t Chirpedpulse t t t Thispulsesumswiththebluepartofthechirpedpulse Thispulsesumswiththegreenpartofthechirpedpulse Tworeplicasofthepulseareproduced eachfrequencyshiftedbyadifferentamount PerformingSIonthesetwopulsesyieldsthedifferenceinspectralphaseatnearbyfrequencies separatedbydw Thisyieldsthespectralphase Inputpulses Outputpulses IaconisandWalmsley JQE35 501 1999 SFG HowSPIDERworks Spectrometer SHGcrystal Filter FocusingLens Lens DelayLine DelayLine Grating Gr