Photonics: A More Sensitive Device

IME researchers have developed a CMOS-compatible scheme for realising surface plasmon polariton (SPPs) in a waveguide Ge-on-SOI photodetector. The proposed photodetector uses Ge as the light absorbing layer and Al grating structure in the CMOS fabrication process. The SPP augments the interaction between light and the Ge layer, while the grating structure excited SPPs and delays light propagation properties. The resulting photodetector exhibits 3x higher transverse magnetic mode responsivity than that of transverse electric modes - demonstrating that an additional dimension can be used to improve performance in waveguide photodetectors. The photodetector can be applied in wavelength division multiplex networks for high speed data communication.