Nanoantenna-Enhanced Palladium Diselenide Mid-Infrared Photodetector

This design proposes a palladium diselenide (PdSe2) photodetector with integrated metallic nanoantennas, which is capable of detecting light in the 5-8 mu m wavelength range. PdSe2 is an attractive material for mid-infrared (MIR) photodetection owing to its large bandgap tunability and high mobility. The metallic nanoantennas simultaneously improve both light absorption and photocarrier collection. Simulation results show that the responsivity is enhanced by the nanoantennas by 9 times and reaches 1 A/W. Besides, the polarization-dependent enhancement by the nanoantennas improves the polarization ratio to 4.2. The results indicate that this design has the potential to achieve high-responsivity and polarization-sensitive on-chip MIR photodetectors.