简介:Weproposeaphotonicstructurestackedsequentiallybyone-dimensionalphotoniccrystalsandcavities.Thewholestructureiscomposedofsingle-negativeanddouble-negativematerials.TheopticalWannier–Starkladder(WSL)canbeobtainedinalowfrequencyregionbymodulatingthewidthsofthecavitiesinorder.Wesimulatethedynamicalbehavioroftheelectromagneticwavepassingthroughtheproposedphotonicstructure.Duetothedispersivecharacteristicsofthemetamaterials,averynarrowWSLcanbeobtained.Thelong-periodelectromagneticBlochoscillationisdemonstratedtheoreticallytohaveaperiodonamicrosecondtimescale.
简介:WestudytheboundedandthecompactweightedcompositionoperatorsfromtheBlochspaceintotheweightedBanachspacesofholomorphicfunctionsonboundedhomogeneousdomains,withparticularattentiontotheunitpolydisk.Forboundedhomogeneousdomains,wecharacterizetheboundedweightedcompositionoperatorsanddeterminetheoperatornorm.Inaddition,weprovidesufficientconditionsforcompactness.Fortheunitpolydisk,wecompletelycharacterizethecompactweightedcompositionoperators,aswellasprovide'computable'estimatesontheoperatornorm.