Waveguide-integrated PdSe2 photodetector with high responsivity and speed in the near-infrared range across the O+E+S+C bands

Abstract

Hybrid integration of two-dimensional (2D) materials on a silicon photonic platform enables diverse exploration of novel active functions and significant improvement in device performance for next-generation silicon integrated photonic circuits. 2D transition metal dichalcogenide materials (TMDCs) have attracted extensive attention for photodetectors, but developing high-performance waveguide-integrated photodetectors based on conventionally investigated 2D TMDCs at the telecom C-band is still a big challenge because of their large optical bandgap and slow carrier mobility. Here, we propose PdSe2, a new type of 2D TMDC, to be integrated with silicon photonic components for on-chip photodetection with high responsivity and speed in the datacom and telecom optical bands ranging from the O-band to the C-band. The obtained waveguide-integrated photodetectors show a high responsivity of 1190.2 mA W−1 at 1550 nm and a low noise-equivalent power of 4.0 pW Hz-0.5 at 5V. The 3 dB bandwidth reaches up to 1.5 GHz, and the measured data rate is 2.5 Gbit s−1. The achieved PdSe2 photodetectors provide new insights to explore the integration of novel 2D TMDCs with silicon photonics and demonstrate the potential of integrated photodetectors for applications in diverse areas, including optical communications, on-chip spectroscopy, and sensing.