Cascaded Fabry-Perot cavity photodetector for flat-top steep-edge spectral response

This paper discussed a novel photodetector with a flat-top and steep-edge response, which is promising for WDM application. The novel detector utilizes an inclined mirror and a multi-cavity filter and is proposed based on the ITMTMC (Inclined Top Mirror and Three-Mirror-Cavity) photodetector. This structure uncouples the quantum efficiency and the spectral response linewidth which has the properties of high response speed, high quantum efficiency and narrow linewidth. Effects of the device parameters such as area, inclined angle and layer-thickness error on the response are investigated. Finally, the tuning ability of this device is also analyzed.