简介:Weproposeaphotonicstructurestackedsequentiallybyone-dimensionalphotoniccrystalsandcavities.Thewholestructureiscomposedofsingle-negativeanddouble-negativematerials.TheopticalWannier–Starkladder(WSL)canbeobtainedinalowfrequencyregionbymodulatingthewidthsofthecavitiesinorder.Wesimulatethedynamicalbehavioroftheelectromagneticwavepassingthroughtheproposedphotonicstructure.Duetothedispersivecharacteristicsofthemetamaterials,averynarrowWSLcanbeobtained.Thelong-periodelectromagneticBlochoscillationisdemonstratedtheoreticallytohaveaperiodonamicrosecondtimescale.
简介:Weexperimentallydemonstratetheopticalpropertiesofgratingsengravedinasingle-modewaveguidefabricatedontopofadielectricmultilayerplatform.ThestructurecanbeapproachedasareflectorforBloch-surface-wavebasedtwo-dimensionalopticalsystems.Thegratingshavebeenfabricatedonathin(~λ∕25)titaniumdioxidelayerwithathicknessofafewtensofnanometersdepositedonthetopofamultilayerplatform.Theopticalpropertiesofthegratingshavebeencharacterizedinthenearfieldwiththeaidofmulti-heterodynescanningnearfieldopticalmicroscopy.Weinvestigatethesurfacewave’sinterferencepattern,producedbyincidentandreflectedlightinfrontofthegratings.ThepresentedgratingsbehaveasanefficientBloch-surface–wave-basedreflectorattelecommunicationwavelength.
简介:Strongnonlinear,electro-optical,andthermo-opticalpropertiesoflithiumniobate(LN)havegainedmuchattention.However,theimplementationofLiNbO3inrealdevicesisnotatrivialtaskduetodifficultiesinmanufacturingandhandlingthin-filmLN.Inthisstudy,weinvestigateanopticaldevicewheretheBlochsurfacewave(BSW)propagatesonthethin-filmLNtounlockitsproperties.First,accesstotheLNfilmfromair(oropenspace)isimportanttoexploititsproperties.Second,forsustainingtheBSW,one-dimensionalphotoniccrystal(1DPhC)isnecessarytobefabricatedunderthethin-filmLN.Weconsidertwomaterialplatformstorealizesuchadevice:bulkLNandcommercialthin-filmLN.Clearreflectancedipsobservedinfar-fieldmeasurementsdemonstratethepropagationofBSWsontopoftheLNsurfaceofthedesigned1DPhCs.