Influence of anomalous dispertion layer thickness and position on optical absorption and quantum efficiency in the resonant-cavity detector

We present a theoretical analysis on the optical absorption and quantum efficiency (QE) of a resonant cavity enhanced InGaAs/GaAs P-i-n photodetector (RCE PD). The QE is calculated by using transfer matrix method that includes the structural parameters of the RCE PD and takes into account the standing wave effect and a energy conservation law is offered. Using anomalous dispersion (AD) mirror flattopped QE spectrum has been obtained. The influence of the thickness and position of AD layer on the optical absorption and QE are shown and design with a maximum QE of 92.5% and 6 nm spectral flattop are presented.