Growth,+thermal+properties+and.ppt

Highefficient1.56mlaseroperationofCzochralskigrownEr:Yb:Sr3Y2(BO3)4crystal,胡杰120420164,Outline,AbstractIntroductionExperimentResultsanddiscussionsConclusion,Abstract,AnEr:Yb:Sr3Y2(BO3)4crystaldopedwith0.9at.%Er3+and18.6at.%Yb3+ionswasgrownbytheCzo-chralskimethod.End-pumpedbydiodelaserat970nminahemisphericalcavity,1.3Wquasi-cwlaseroutputaround1.56mwasachievedina1.1-mm-thickZ-cutEr:Yb:Sr3Y2(BO3)4crystalwhenthetransmissionofoutputcoupleris1.5%.Theabsorbedpumpthresholdandslopefficiencyofthelaserare4.26Wand20%,respectively.Thiscrystalhasflatandbroadgaincurvepeakedaround1.56m,whichshowsthatitisalsoapotentialgainmediumfortunableandshortpulselasers.,Introduction,Erbiumlaserat1.5-1.6mviathe4I13/24I15/2transitionhasmanypracticalapplications.Yb3+ionswithlargeabsorptioncross-sectionaround980nm,theemissionwavelengthofInGaAsdiodelaser,aregenerallyco-dopedassensitizertoimprovethepumpefficiency.Er3+andYb3+co-dopedboratecrystals,suchasYAl3(BO3)4GdAl3(BO3)4,YCa4O(BO3)3,andGdCa4O(BO3)3crystalshavebeendemonstratedtobeefficientgainmediaforthe1.5-1.6mlaser.,However,theYABandGABcrystalscanonlybeobtainedbythefluxmethodwithalonggrowingperiod.AlthoughtheYCOBandGCOBcanbegrownbytheCzochralskimethod,whichisoneofthetechniquesforgrowinglargesinglecrystalswithgoodopticalqualityinashortperiod,thepeakabsorptioncross-sectionsaround976nmoftheEr3+andYb3+co-dopedYCOB(0.910-20cm2)andGCOB(1.1510-20cm2)crystalsaresmallandthefullwidthsathalfthemaximum(FWHMs)oftheabsorptionbandsarenarrow.TheM3Re2(BO3)4(M=Ca,Sr,Ba;andRe=Y,Gd,La)crystalscanbegrownbytheCzochralskimethod.IthasbeenshownthatYb3+ionsdopedinthesecrystalshavelargerabsorptioncross-sectionandbroaderabsorptionbandaround976nmthanthoseoftheYCOBandGCOB,Experiment,配料,研磨,烧结,生长,装炉,重复,基座,石英管,氧化锆填充料,坩埚,射频感应圈,熔体,晶体,观察孔,保温罩,提拉杆,Pullrate12mm/hRotaterate1020rpmAnnealingrate1030C/h,Er3+/Yb3+:SYB,Resultsanddiscussions,Fig.1.RTpolarizedabsorptionspectraofEr:Yb:SYBcrystalinarangeof8501070nm,Fig.2.RTpolarizedabsorption(a)andemissionspectra(b)ofEr:Yb:SYBcrystalinarangeof14001670nm,Fig.3.Gaincurvesofthe4I13/24I15/2transitionofEr3+ionsinEr:Yb:SYBcrystalforE/YwithdifferentandforE/X,E/YandE/Zwhenis0.5,Fig.4.Laseroutputpowerat1.5-1.6masafunctionofabsorbedpumppowerat970nm,absorbedpumpthresholdpower,4.26W,3.9W,1.13W,1.3W,Fig.5.SpectraoftheEr:Yb:SYBlaserat1.5-1.6mwhentheabsorbedpumppoweris10.86Wandoutputcouplertransmissionsare:(a)T=1.0%,(b)T=1.5%.,Conclusion,1.3Wquasi-cwlaseroutputaround1.56mwithaslopefficiencyof20%wasachievedinEr:Yb:SYBcrystalgrownbytheCzochralskimethod.Bymeansoftheintracavityfrequencydoublingtechnique,thelinearlypolarized1.56mlasercanbefurthereffectivelyconvertedinto780nmlaser,whichhassomeimportantapplicationsasmentionedabove.Itisworthnotingthattheabsorptioncross-sectionoftheEr:Yb:SYBcrystalat976nmistwiceasthatatthepumpwavelengthof970nminthiswork(seeFigure1)Therefore,ifapumpsourcearound976nmisused,thelaserperformanceofathinnerEr:Yb:SYBmediumcouldbeimproved.Furthermore,largesingleEr:Yb:SYBcrystalcanbegrowtheasilyinashortperiodviatheCzochralskimethod.Combiningwiththesuitabil