Theoretical analysis of GaAs-based Fabry-Perot cavity filter and its application in integrated photodetector

摘要

A kind of GaAs-based F-P(Fabry-Perot) cavity filter was presented. Its structure and tunability were analysed theoretically. Numerical simulation shows transmitted centre wavelength of the filter is 1.55μm, FWHM is 1.8nm and 0.6nm with 17 and 23 pairs of DBR respectively, a red shift of 7.2nm with temperature change of 100K, transmissivity almost keeps unchanged during tuning, and tuning wavelength is linear to temperature change. Further, long-wavelength-absorbed integrated photodetectors based on this filter structure was fabricated. Experimental results show a tuning wavelenghth of 10.2nm with power change of 200mW applied to the device, FWHM of about 0.6nm, and 4% quantum efficiency fluctuation during tuning. Good agreement with the simulation has been achieved.