简介：Therelativebandgapforarhombuslatticephotoniccrystalisstudiedbyplanewaveexpansionmethodandhighfrequencystructuresimulator(HFSS)simulation.GeneralwavevectorsinthefirstBriliouinzonearederived.Therelativebandgapasafunctionofair-fillingfactorandbackgroundmaterialisinvestigated,respectively,andthenatureofphotonicbandgapfordifferentlatticeanglesisanalyzedbythedistributionofelectricenergy.Theseresultswouldprovidetheoreticalinstructionfordesigningopticalintegrateddevicesusingphotoniccrystalwitharhombuslattice.

简介：Wedemonstrateaphotonicbandgap(PBG)fromone-dimensional(1D)periodicstructurescreatedbyadouble-layerunitcellwithanairlayerandananisotropicnonmagneticleft-handedmetamaterial(LHM)layerwhosepermittivityelementsarepartiallynegative.TherequirementsimposedonthematerialsandstructurestorealizeaPBGarederivedwhenthefrequencyisaboveorbelowthecutofffrequency,andthetransmissionpropertiesofthePBGarediscussedbyutilizing4×4transfer-matrixmethodwithdispersivesemiconductormetamaterial.

简介：Higher-bandself-trappingandoscillation(rotation)ofnonlinearquadruplebeamsintwo-dimensional(2D)squarephotoniclatticesarenumericallydemonstrated.Underappropriateconditionsofnonlinearity,aquadruple-likebeamcanself-trapintolocalizedmodesthatresideinthesecondBraggreflectiongapthroughsingle-siteexcitation.Bychangingtheinitialorientationoftheincidentquadruplebeamrelatedtothelattices,periodicoscillationsofthelocalizedquadruplemodemaybeobtained.Thelocalizedquadruplestatebecomesarotatingdoublychargedopticalvortex(DCV)duringrotationandshouldundergocharge-flippingwhentherotatingdirectionisreversed.