High-finesse resonant-cavity photodetectors with an adjustable resonance frequency

High speeds, high external quantum efficiencies, narrow spectral linewidths, and convenience in coupling make resonant-cavity photodetectors (RECAP's) good candidates for telecommunication applications. In this paper, we present analytical expressions for the design of RECAP's with narrow spectral linewidths and high quantum efficiencies. We also present experimental results on a RECAP having an operating wavelength lambda(0) approximate to 1.3 mu m with a very narrow spectral response, The absorption takes place in a thin In0.53Ga0.47As layer placed in an InP cavity, The InP p-i-n structure was wafer bonded to a high-reflectivity GaAs/AlAs quarter-wavelength Bragg reflector, The top mirror consisted of three pairs of a ZnSe/CaF2 quarter-wavelength stack (QWS), A spectral linewidth of 1.8 nm was obtained with an external quantum efficiency of 48%, We also demonstrate that the spectral response can be tailored by etching the top layer of the microcavity, The results are found to agree well with those obtained from analytical expressions derived on the assumption of linear-phase Bragg reflectors as well as detailed simulations performed using the transfer matrix method.