Two-dimensional Platinum Diselenide Waveguide-Integrated Infrared\n Photodetectors

Abstract

Low cost, easily integrable photodetectors (PDs) for silicon (Si) photonics\nare still a bottleneck for photonic integrated circuits (PICs), especially for\nwavelengths above 1.8 ${\\mu}$m. Multilayered platinum diselenide (PtSe$_2$) is\na semi-metallic two-dimensional (2D) material that can be synthesized below\n450${\\deg}$C. We integrate PtSe$_2$ based PDs directly by conformal growth on\nSi waveguides. The PDs operate at 1550 nm wavelength with a maximum\nresponsivity of 11 mA/W and response times below 8.4 ${\\mu}$s. Fourier\ntransform infrared spectroscopy (FTIR) in the wavelength range from 1.25\n${\\mu}$m to 28 ${\\mu}$m indicates the suitability of PtSe$_2$ for PDs far into\nthe infrared wavelength range. Our PtSe$_2$ PDs integrated by direct growth\noutperform PtSe$_2$ PDs manufactured by standard 2D layer transfer. The\ncombination of IR responsivity, chemical stability, selective and conformal\ngrowth at low temperatures, and the potential for high carrier mobility, make\nPtSe$_2$ an attractive 2D material for optoelectronics and PICs.\n