Room-temperature waveguide-coupled silicon single-photon avalanche diodes
Alperen Gövdeli, John N. Straguzzi, Zheng Yong, Yiding Lin, Xianshu Luo, Hongyao Chua, Guo‐Qiang Lo, Wesley D. Sacher, Joyce K. S. Poon
Abstract
Abstract Single photon detection is important for a wide range of low-light applications, including quantum information processing, spectroscopy, and light detection and ranging (LiDAR). A key challenge in these applications has been to integrate single-photon detection capability into photonic circuits for the realization of complex photonic microsystems. Short-wavelength ( λ < 1.1 μm) integrated photonics platforms that use silicon (Si) as photodetectors offer the opportunity to achieve single-photon avalanche diodes (SPADs) that operate at or near room temperature. Here, we report the first waveguide-coupled Si SPAD. The device is monolithically integrated in a Si photonic platform and operates in the visible spectrum. The device exhibited a single photon detection efficiency of >6% for wavelengths of 488 and 532 nm with an excess voltage of <20% of the breakdown voltage. The dark count rate was below 100 kHz at room temperature, with the possibility of improving by approximately 35% by reducing the temperature to −5 °C.