基于周期極化鈮酸鋰的電光開關研究.pdf

1、天津大學碩士學位論文基于周期極化鈮酸鋰的電光開關研究姓名：紀磊申請學位級別：碩士專業(yè)：物理電子學指導教師：于建20030101AbstractLithiumniobatecrystalhasaseriesofoutstandingpropertiesofelectroopticsacousticopticsplasticopticspizoelectronicspyroelectricityandnonlinearopticswhich

2、makeitoneofthemostatractivematerialsforacousticopticalelectroopticalandnonlinearopticaldevices.Thelargestnonlinearcoefficientoflithiumniobated33(25.2pmV)，whichisutilizedinperiodicallypoledlithiumbiobateexploitingquasipha

3、sematchingandcascadedsecondordernonlinearprocessforparametricprocesssuchassecondharmonicgenerationdiferentialfrequencygenerationopticalparametricoscillationhasanidealtuningproperties.WeintroduceelectroopticseffectintoPPL

4、NwavelengthconverterinordertoachieveanelectricallycontrollednsorderallopticalswitchonbasedonPPLN.Theworkisbasedonthisideamakingsomecontributiontorelatedtheoreticalanalysisandsomeprocessimprovement.Majorcontributionisasfo

5、llows:1.ThemodalcharacteristicsofmetalcladwaveguideareinvestigatedwithFEMinthisthesistodirectthedefinitionofgeometryparameterofourdevice.Wegetsomenewconclusionsfromcomputationalresult:ThephenomenaofTMmodeevolutionduringt

6、hevariationofthethicknessofbuferlayerAlthoughthehigherlosscharacteristicsofTMmodeshouldbeavoidedinelectricallycontrolledswitchitisbeneficialforhighperformancepolarizor.Multipleplasmasurfacemodesisobservedin2dimensionalre

7、ctangularwaveguide.2.ThespaceharmonicanalysisofQPMisderivedindetailinthisthesisaelectricalmodalofcrystalunderdomainreversalprocessisalsogiven.Ajigforliquidelectrodepolingprocessisrevisedinordertoimprovethequalityofdomain

8、reversalprocess.Atthesametimethenecessityofrealtimemonitoringisemphasized.Twoschemesofrealtimemonitoringisintroducedtheschemeexploitingelectroopticalefectoflithiumniobatecrystalisinterpreted.3.Theinitialproposalofelectro

9、opticalswitchisreobservedanditisprovedtobelackoffeasibility.Furthertwonewschemesareproposedanddetailedlyanalyzedinthis.thesisKeyWords:electroopticalswitchintegratedopticsmetalcladwaveguidefiniteelementmethodquasiphasemat