High-Performance Photodetection Enabled by Lithium Niobate and BP Hybrid Waveguide

A hybrid waveguide composed of lithium niobate and black phosphorus (BP) exhibits a remarkable absorption coefficient of 1.56 dB/µm, exceeding that observed in III-V/TFLN integrated photodetectors. This device further displays a responsivity of 2.64 A/W when operating with an input optical power of 25.1 µW and demonstrates an expansive 3 dB bandwidth of 1.97 GHz at a bias voltage of 1.6 V. These findings strongly suggest that the aforementioned hybrid waveguide holds significant potential for realizing high-performance photodetection applications. The enhanced optical absorption and broadband response characteristics of the lithium niobate and BP hybrid waveguide stem from the synergistic combination of their respective properties. Lithium niobate, known for its excellent electro-optic properties, facilitates efficient light manipulation and control, while BP's unique electronic band structure enables strong light absorption across a broad spectral range. The integration of these materials into a single waveguide structure not only optimizes light absorption but also facilitates efficient charge carrier transport, leading to the observed high responsivity and broad bandwidth.