铌酸锂晶体的研究与分析样本.doc

摘要本文基于新型线性电光效应耦合波理论，通过设定超晶格周期极化铌酸锂晶体倒格矢参数，从而弥补双折射时o光和e光折射率不同导致相位失配。计算有效电光系数，推倒耦合波方程解析解。并运用matlab进行线性仿真，研究温度，波长，外加电场和晶体占空比变化时对于电光效应中转换效率影响。仿真数值成果表白：随着温度与相位匹配时相应温度差值增大，相位失配量将增长，从而导致转换效率呈峰值逐渐减少波动形式趋于零，当温度满足相位匹配时转换效率最高；此外晶体极化周期数量增长，将使得转换效率波动更加激烈，其值也减少更快，波动次数也将增多。变化波长状况基本类似于温度，仅在波动细节上有细微差距。而电场对转换效率影响则是成正比线性关系。此外咱们所取占空比约等于0.25和0.75时将可以使转换效率取到最大值。核心词铌酸锂；电光效应；耦合波；转换效率AbstractBasedonthenewwavecouplingtheoryoflinearelectro-opticeffect.BysettingthegratingwavevectorparametersofperiodicallypoledLiNbOcrystal，wecompensateforthephase-matchedwhichiscausedbydifferentindexofrefractionoftheo-rayande-raywhenbirefringencehappens.Wecancalculatetheeffectiveelectro-opticcoefficientofthesystem.Throughtheanalyticalsolutionofthewavecouplingequations，usematlabtodolinearsimulation，andstudyontheinfluenceoftheconversionefficiencyintheelectro-opticaleffectwhentemperature，wavelength，electricfieldintensityandcrystaldutycyclechange.Numericalsimulationresultsshowthat，withtheincreasingdifferencemadebytemperaturewhichcorrespondstothetemperatureandphasematching，theamountofphasemismatchwillincrease.itresultsinanincreaseofHYPERLINK"+mismatch"phasemismatch，thuscausingtheconversionefficiencytoassumethefluctuatingformtendingtozerowhichthepeakvaluereducesgradually；whenthetemperaturesatisfiesphasematch，conversionefficiencyisthehighest.Inadditionwhenthenumberofthecrystalpolarizationcycleincreases,thefluctuationoftheconversionefficiencywillbemoreviolent,thevaluewillalsoreducefasterandthenumberoffluctuationswillincrease.Thesituationofthewavelengthissimilarwiththetemperature.Thereisjustonlylittlediscrepancyonthefluctuationindetailsoftheconversionefficiency.Buttheinfluenceoftheelectricfieldtotransferefficiencyistheproportionallinearrelationship.Inaddition，whenthedutycycleisequivalenttoabout0.75and0.25,theconversionratecanbetakentothemaximum.KeywordsLiNbO；electro-opticaleffect；coupledwave；conversionefficiency目录TOC\o"1-3"\h\z\uHYPERLINK\l"_Toc"摘要PAGEREF_Toc\hIHYPERLINK\l"_Toc"AbstractPAGEREF_Toc\hIIHY