简介：Inthispaper,wepresentanultra-compact1Dphotoniccrystal(PhC)Bragggratingdesignonathinfilmlithiumniobateslotwaveguide(SWG)via2D-and3D-FDTDsimulations.2D-FDTDsimulationsareemployedtotunethephotonicbandgap(PBG)size,PBGcenter,cavityresonancewavelength,andthewholesizeofPhC.3DFDTDsimulationsarecarriedouttomodeltherealstructurebyvaryingdifferentgeometricalparameterssuchasSWGheightandPhCsize.AmoderateresonancequalityfactorQofabout300isachievedwithaPhCsizeofonly0.5μm×0.7μm×6μm.TheproposedslotBragggratingstructureisthenexploitedasanelectricfield(E-field)sensor.Thesensitivityisanalyzedby3D-FDTDsimulationswithaminimumdetectableE-fieldassmallas23mV∕m.Thepossiblefabricationprocessoftheproposedstructureisalsodiscussed.ThecompactsizeoftheproposedslotBragggratingstructuremayhaveapplicationsinon-chipE-fieldsensing,opticalfiltering,etc.