Study on Crosstalk Reduction in Resonant-Cavity-Enhanced PD-Array for WDM-beam direct detection

In this study, we present a resonant cavity-enhanced two-dimensional-photodetector (PD) array device, which can receive four different wavelengths simultaneously in free space. A different wavelength sensitivity in each resonant PD pixel allows de-multiplexing wavelength in wavelength division multiplexing (WDM) beam signal in free space. We discuss the crosstalk reduction design in the PD array for 4-WDM FSO beam direct detection and its fabricated device performance.