发光二极管的时间与空间相干性研究

:025827025(2005)0120031204,,,,3(,510275)(LED),LEDLED;;LEDLED,LED;;;;;TN312+.8;TN241AStudyofTemporalandSpatialCoherenceofLightEmittingDiodeLIJun2tao,ZHUJian,WANGZi2xin,LIMing,ZHOUJian2ying(TheStateKeyLaboratoryofOptoelectronicMaterialsandTechnologies,SunYat2senUnivisity,Guangzhou,Guangdong510275,China)AbstractThetemporalandspatialcoherenceoflightemittingdiode(LED)isstudiedbyMichelsoninterferometerwithsubfemtosecondtimeresolution.LEDsspectralcharacteristicsandcoherencetimearemeasured,andtheiremittingareaisestimatedbyLEDsinterferencesignal.Systematicerrorsintheexperimentsarediscussedandthesolutionstoreducetheerrorsaresuggested.ResultsshowthatLEDcanbeappliedasalightsourceforstableandtimeresolvedspectroscopy.Keywordslaserphysics;degreeofcoherence;Michelsoninterferometer;lightemittingdiode;temporalcoherence;spatialcoherence:2003207203;:2004201205:(90201027,10374120):(1980),,,,E2mail:[e-mail]3E2mail:[e-mail]1(LED),50,[1]LED,LED,LED,LED,LED2,,,,,,,32120051CHINESEJOURNALOFLASERSVol.32,No.1January,2005©1995-2005TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.,,,,,1P2Fig.1Temporal2spatialcoherenceinpointPE1(r1,t1)E2(r2,t2)P,1,P[2]IP=I1+I2+2I1I2Re{12()},(1)I1=E21,I2=E22,E1,E2S1,S2P,12(),S1,S2,12():1)12()1,;2)012()1,;3)12()0,,11(),12(0)VanCittert2Zernike[3]12()=11()12(0),(2)/-n1n1,(3),-LED,:1012Hz,-1015Hz,50fs,(3)LED,(2),V[2]V=Imax-IminImax+Imin=2I1I2I1+I212(),(4)Imax,IminI1=I2,V()=12()=11()12(0),(5)LED,,,;LED,LED3311LED2LED;S1320;He2Ne,,M4,LED;WSM2200,,0102m,011fsM1,M2,LEDLEDLED,,LED204URCLED,GaAs0.6P0.4/GaP,650nm,18nm,LED20mA2LEDFig.2SchematicexperimentalsetupforthemeasurementoftheLEDtemporalcoherenceLED,,LED,2332©1995-2005TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.312,d,dLm,[4]Lm=2/,(6),o=Lm/c=2/(c),(7)[3]o=t=+-11()d=11()(8),He2Ne,,LED,,3,;;13,3LEDFig.3InterferencesignalofLED,[5]WDG30,44cm-1,,4,,LEDLED,LED3ImaxImin(4)LEDV12(),5,LED11(),5511()(7)78132fs4(8)78149fs,4LEDFig.4PhotoelectriccharacteristicofLED5LEDFig.5DegreeofcoherenceofLED6Fig.6Influenceofspatialcoherence3.36LED,,,511()331:©1995-2005TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.12()(5)LED12(0)01791,LED0179,LED,LED6,LED,[4]12(0)=sin(/)H(/)H,(9),H,=H/F,FLED650nm,F=10cm,512(0)=0179(9)H=0115mm,LED013mm013mm,LED,,LED,,,LED3.4LED100fs,800nm10nm[6],LED,7LEDNd3+Fig.7InterferogramofNd3+byLEDLED50fsLED,Nd2O3HNO3Nd3+,7NdYAG[7],LED4LED,LEDLED,LED,LED,,LED,,LED1FangZhilie.SemiconductorLightEmittingMaterialandDevice[M].1sted..Shanghai:FudanUniversityPress,1992.275316.[M].1:,1992.2753162LiuSimin,XuJingjun,GuoRu.CoherentOptics2FundamentalsandApplications[M].2nded..Tianjin:NankaiUniversityPress,2001.1718,,.[M].1:,2001.17183J.Perina,TranslatedbyZhanDasan.CoherenceofLight[M].1sted..Beijing:SciencePress,1986.2123J.,.[M].1:,1986.21234LiLiangde.BasalOptical[M].1sted..Guangzhou:SunYat2senUnivisityPress,1987.169189.[M].1:,1987.1691895ZhangGuangzhao.FourierTransformSpectroscopy[M].1sted..Guangzhou:SunYat2senUnivisityPress,1988.4447.[M].1:,1988.44476ChenLei,LuoLi,DaiDechangetal..Experimentaltechniquesforquantumwavepacketinterferometer[J].ChineseJ.Lasers,2001,A28(2):142145,,.[J].,2001,A28(2):1421457Q.Luo,D.C.Dai,G.Q.Wangetal..Theoryandexperimentofcoherentwavepacketdynamicsinrareearthsolids:Absorptionspectrumvsfemtosecondfringe2resolvedinterferogram[J].JournalofChemicalPhysics,2001,114(4):187018754332©1995-2005TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.