飞秒激光脉冲诱导透明介质的非线性吸收和折射率改变轮廓研究

3(:No.60078004)863(No.2000210)Tel:[phone]Email:[e-mail]:200212163(,710068),;,,,1,,,;1;;;O437A0,,,,[1]1,[2],[3]1,,,,[4,5]1,,,,110.65NA800nm110fs,2mm,11,,50/50,,,,,,,,10.02J,,;0.02J,,,,;,10.3J,0.3,;,,,11Fig.1Thenonlinearabsorptionoffusedsilicainducedbyfemtosecondlaserpulse1,,T,E,I,:logT=-0.4logE-0.638,:logT=-0.4logI+5.15,,0.020.3J11-T,:=1-10-014logI+5.1513211200311ACTAPHOTONICASINICAVol.32No.11November2003[8],,,,;,(10181020/cm3),,1,,,1,20%;,1,,12,,112.11,;,,,1(SiO2),E9eV,E=h,140nmSiO2,1800nm,SiO216,,1Ik,1[6]ddt29m3/2e216nc0mE2I(t,z)6exp(12)26-E(1),n,c,m2,k,,(x)Dawson(x)=exp(-x2)x0exp(y2)dy=exp(-x2)6r=0x2r+1r!(2r+1)(2)100fs,,k,,1,,1,Dawson,,IrI=exp(-2r/r0)2(3)r01r(I/E)kexp(2k)(4),,1021cm-1,(micro2explosions)(ablation)12.2,:0.65,800nm,100fs,1261,1/e21/e2,800nm,1/2500nm;,1/2320nm,(400nm800nm);6(),1/2200nm1[7]1,1/21,1,,(),;,,12Fig.2Thedensitydistributionoffreeelectronplasmainducedbyfemtosecondlaserpulse2821323(),rz,,(XY)(Gaussian),z(Lorentzian)[8],II(r,z)=I0(r0/(z))2exp[-2(r/(z))2]I0;r01(z)=r01+(z/z0)2,z0=nr0/Rayleigh,n,113,(a)k=1;(b)k=6,I0=1014W/cm21,,,XZ,,()1rz,[9],1=1-10-0.4logI+5.15,(4)1,,,;I01015W/cm2,;,Z,Raylengh,5,()1n(I)=n0+n2I(n0,n23Fig.3Thedistributionofplasmadensityinconfocalvolume4Fig.4Thedistributionofplasmadensityconsideringnonlinearabsorption51016W/cm2Fig.5ThedistributionofplasmadensityatI0=1016W/cm2,,n2=2.410-16cm2/W),,Rayleigh,Rayleigh,,,[10]16NA=0.65,5m16Fig.6Theconfigurationofrefractiveindexchange382111.,,(E,[11]),1,,,,,6(c)1,,[7]1,,,;(NA=0.65,500m)1,,()14m,[2]14,,,,:,,,,;5,,Rayleigh,1X,,11ChengGuanghua,WangYishan,WhiteJD,etal.Demonstrationofhigh2densitythree2dimensionalstorageinfusedsilicabyfemtosecondlaserpulses.JofApplPhys,2003,accepted2StrltsovAM,BorrelliNF.Studyoffemtosecond2laser2writtenwaveguidesinglasses.JOSA(B),2002,19(10):249625043GlezerEN,MazurE.Ultrafast2laserdrivenmicro2explosionsintransparentmaterials.ApplPhysLett,1997,71(4):8828844FanChH,LongtinJP.Modelingopticalbreakdownindielectricsduringultrafastlaserprocessing.ApplOpt,2001,40(18):312431315DuD,LiuX,KornG,etal.Laser2inducedbreakdownbyimpactionizationinSiO2withpulsewidthsfrom7nsto150fs.ApplPhysLett,1997,33(10):170617166NoackJ,VogelA.Laser2inducedplasmaformationinwateratnanosecondtofemtosecondtimescales:calculationofthresholds,absorptioncoefficients,andenergydensity.IEEEJofQuantElec,1999,35(8):115611677LuoL,WangDL,LiCD,etal.Formationofdiversiformmicrostructuresinwide2bandgapmaterialsbytight2focusingfemtosecondlaserpusles.JOpt(A)PureApplOpt,2002,4(1):1051108HanschP,WalkerMA,WoerkomLDV.Spatiallydependentmultiphotonmultipleionization.PhysicssReview(A),1996,54(4):R2559R25639,,,..,2003,32(3):276279LiuQ,ChengGH,WangYS,etal.ActaPhotonicSinaca,2003,32(3):27627910YauTW,LeeCH,WangJ.Uncollapsedselffocusingoffemtosecondpulsesindielctricmediaduetothesaturationofnonlinearrefractiveindex.CLEO,200011311kajiharaK,IkutaY,HiranoM,etal.PowerdependenceofdefectformationinSiO2byF2laserirradiation.ApplPhyLett,2002,81(17):31643166482132TheNonlinearAbsorptionandConfigurationofRefractiveIndexChangesofFusedSilicaInducedbyFemtosecondLaserPulseChengGuanghua,LiuQin,YangLingzheng,WangYishan,DongShufu,ZhaoWei,ChenGuofuStateKeyLaboratoryofTransientOpticsandTechnology,XianInstituteofOpticsandPrecisionMechanicsChineseAcademyofSciences,Xian710068ChinaReceiveddate:20021216AbstractThenonlinearabsorptionoffusedsilicainducedbyfemtosecondlaserpulsesisinvestigatedexperimentally.Basedontherelationbetweenrefractiveindexchangeswithplasmadensity,theconfigurationofrefractiveindexchangesissimulatedanalytically.Andsuggestingthatmicro2fabricationusingfemtosecondlaserpulsescanbreakdownRayleighlimit,andrealizenanometerordermaterialprocessing.KeywordsNonlinearabsorption;Femtosecondlaserpulse;Fusedsilica;RefractiveindexChengGuanghuawasbornin1976,andreceivedhisB.S.degreefromtheDept.ofPhysics,NorthwestUniversityin1995.NowheiscurrentlyworkingasaPh.D.candidateattheStateKeyLaboratoryofTransientOpticsTechnology,XianInstituteofOpticsandPrecisionMechanics,ChineseAcademyofSciences.Hisresearchinterestsarenonlinearoptics,ultra2shortpulsegeneration,lasermaterialprocessing,andthree2dimensionopticaldatastorage.582111.