Designandanalysisofresonantcavity-enhancedquantumringinter-subbandphotodetectorwithresonanttunnelingbarriersforterahertzdetection

TheeffectofresonantcavitystructureontheperformanceoperationofInAs/GaAsquantumringinter-subbandphotodetectorisstudiedfordetectionofterahertzradiationsrange.Inordertoconfinementofopticalfieldwithinactiveregionandconsequentlyenhancementinresponsivityofdevice,twoperiodsofAl2O3/GaAsdistributedbraggreflectorsareusedasbottomdielectricmirrorandathinlayerofAumaterialastopmirrorofdevice.Forfurtherimprovementindetectivity,Al0.3Ga0.7As/In0.3Ga0.7Asresonanttunnelingbarriersareincludedinabsorptionlayerstoreducedarkcurrentofdevice.Proposedphotodetectorshowsapeakresponsivityofabout0.4(A/W)andquantumefficiencyof1.2%atthewavelengthof80μm(3.75THz).Furthermore,specificdetectivity(D*)ofdeviceiscalculatedandresultsarecomparedtoconventionalquantumringinter-subbandphotodetector.ResultspredictaD*of~1011(cm.Hz1/2/W)fordeviceatT=80KandV=0.4VwhichistwoordersofmagnitudehigherthanthatofconventionalQRIPs.