資源描述:
《鈮酸鋰晶體周期極化及其倍頻特性研究》由會(huì)員上傳分享,免費(fèi)在線閱讀,更多相關(guān)內(nèi)容在學(xué)術(shù)論文-天天文庫(kù)。
1、南開(kāi)大學(xué)碩士學(xué)位論文鈮酸鋰晶體周期極化及其倍頻特性研究姓名:陳亞輝申請(qǐng)學(xué)位級(jí)別:碩士專業(yè):光學(xué)指導(dǎo)教師:姚江宏20040420AbstractInthisdissertation,theperiodicallypoledcharacteristicsofZ-cutLiNb03dopedwith5tool%MgO(Mg:LN)andnear·stoichiometricLiNb03(Mg:SLN)crystalsdoped1.8t001.%MgOwereinvestigated.Thequasi·phase。matehed(QPM)secon
2、dharmonicgeneration(gHG)basedontheperiodicallypoledMg:LNandMg:SLNwerealsoinvestigated.111eresearchfindingsaredescribedinbriefasfollows:(1)ThetunabilityandtoleranceofQPMSHGinthebulkperiodicallypoledMg:LNandMg:SLNwereanalyzedThegratingperiodbandwidthandthepumpedspectralbandw
3、idth[fullwidthathalfmaximum(FWHM)]werefoundtobeinversedwiththeeffectivelengthinQPMSHG.(2)ThccharacteristicsoftheferroelectricdomaininversioninZ-catLiNb03dopedwith5m01.%MgO(Mg:LN)wereexamined.Thelowestpolarizationswitchingfield玩inMg:LNisaboutSkV/mm.Therealignmentprocessofth
4、einternalfieldinMg:LNisalsoinvestigated.Usingthespontaneousdomainsbackswitching,auniformsubmicrondomainpatterningwithaperiodof1.7umwassuccessfullyfabricated.(3)Thedomainreversalcharacteristicsofnear-stoichiometrieLiNb03wereexaminedandtheswitchfieldfor180。ferroelectricdomai
5、nreversalin*henear-stoichiomentLiNb03crystaldecreaseswith[Li]/[Li+Nb】ratio.Thcswitchfieldinthecrystal麗m[Li】/[Nb]ratioequalto49,9%wasonly3.籜kV/ram.(4)FollowingtheLivacancymodel,weexplainthereasonsofthedramaticdecreaseoftheswitchingfieldinMg:LNandMg:SLN.Wethoughtthereducibil
6、ityofLivacancyandanti—siteNbLi”defectsresultsinthedecreaseoftheswitchingfield.(5)Uniformlyperiodicdomainstructureina1.0mmthickslabofMg:LNandMg:SLNwerefabricated.UsingaQ-swilchedNd:YAGlaserasthefundamentalbeamsonreeatt.06a“nl。thegreenSHGat0.532Ⅱmwasobtainedfromperiodicallyp
7、oledMg:LNat1.亭%conversionefficiency.UsingaTi:sapphirelaser,third—orderquasi—phase·matchedsecondharmonicvioletlightgenerationWasdemonstratedinperiodicallypoledMg:SLN,withanenergyconversionefficiencyof20.5%.IIKeywords:Quasi-phase—matched(QPM)TheswitchingfieldSecondharmonicge
8、neration(SHG)PeriodicallypoledlithiumniobatedopedMgOPeriodicallypolednear-stoichiometricl