Sy. Hu et al., COUPLED-CAVITY RESONANT PHOTODETECTORS FOR HIGH-PERFORMANCE WAVELENGTH DEMULTIPLEXING APPLICATIONS, Applied physics letters, 71(2), 1997, pp. 178-180
A new coupled-cavity resonant photodetector structure is studied to pr
ovide a flat-topped passband with steep skirts in the photoresponse. T
he idea is to add a low-loss cavity that is optically coupled to the a
bsorptive cavity via an intermediate mirror. Experimental reflection s
pectra confirm this coupling effect. Modeling for an InGaAs/GaAs/AlGaA
s design reveals that this new coupled-cavity structure will be able t
o show a 22 dB channel rejection ratio even when the optical channel s
pacing is as narrow as 2 nm. In addition, the design and processing to
lerances for cavity-mode adjustment are also addressed. (C) 1997 Ameri
can Institute of Physics.