简介：Thepresentstudydevelopsthefracturetheoryforatwo-dimensionaloctagonalquasicrystals.TheexactanalyticsolutionofaModeⅡGriffithcrackinthematerialwasobtainedbyusingtheFouriertransformanddualintegralequationstheory,thenthedisplacementandstressfields,stressintensityfactorandstrainenergyreleaserateweredetermined,thephysicalsenseoftheresultsrelativetophasonandthedifferencebetweenmechanicalbehaviorsofthecrackproblemincrystalandquasicrystalwerefiguredout.Theseprovideimportantinformationforstudyingthedeformationandfractureofthenewsolidphase.

简介：Anovelpolarizationsplitterbasedonoctagonaldual-corephotoniccrystalfiber(O-D-PCF)isproposed.Theimpactsofseveralfiberparametersonthecouplingcharacteristicsofthepolarizationsplitterareinvestigatedbyfull-vectorialfiniteelementmethod(FV-FEM)indetail.Throughoptimizingthefiberconfiguration,a4.267-mm-longpolarizationsplitterwithabandwidthof37nmisachieved,anditsextinctionratio(ER)isashighas81.2dBatthewavelengthof1.55μm.Comparedwiththehexagonaldual-corephotoniccrystalfiber(H-D-PCF)basedpolarizationsplitter,bothERandbandwidthoftheO-D-PCFbasedoneareeffectivelyimproved.

简介：Hybridoctagonal-ringmicrolasersareinvestigatedforrealizingastableoutputfromasiliconwaveguidebasedonatwo-dimensionalsimulation.Theinnerradiusoftheringisoptimizedtoachievesingle-modeandlow-thresholdoperation.Usingthedivinylsiloxane-benzocyclobutene(DVS-BCB)bondingtechnique,ahybridAlGaInAs/Sioctagonal-ringmicrolaserverticallycoupledtoasiliconwaveguideisfabricatedwithasidelengthof21.6μmandaninnerradiusof15μm.Asingletransverse-modeoperationisachievedwithathresholdcurrentdensityof0.8kA∕cm~2andaside-modesuppressionratioabove30dB,andastableoutputfromthelowersiliconwaveguideisobtained.