Waveguide-Integrated Photodetectors based on 2D Platinum Diselenide

Low cost, easily integrable photodetectors for silicon photonics are still a bottleneck for photonic integrated circuits. Platinum diselenide (PtSe 2 ) is a two-dimensional (2D) transition metal dichalcogenide that has a band gap in the mid-infrared range in mono- and bilayer form and becomes semi metallic as a multilayer material [1] . Multilayer PtSe 2 can be utilized for infrared photodetection [2] . One of its major assets, in particular when it comes to photonics integration, is that it can be grown at Back-end-of-line (BEOL) CMOS compatible temperatures on various substrates using thermally assisted conversion (TAC) [3] , [4] . Here, we demonstrate PtSe 2 photodetectors grown directly on silicon (Si) photonic waveguides at low temperature and compare their performance to PtSe 2 photodetectors fabricated by typical 2D layer transfer at a wavelength of λ = 1550 nm.