Research progress of semiconductor up-conversion single photon detection technology

Quantum communication technology has achieved remarkable progress and development in recent years, and the single photon detector, as the receiving terminal, plays a vital role in communication systems. In this paper, we focus on the current mainstream semiconductor-based single photon detectors and review their device principle, operating mode, advantages and disadvantages. Besides, the research progress of a novel semiconductor near-infrared single photon detection technology (USPD) is introduced. The feasibility and superiority of the USPD device are demonstrated from the basic principle, device structure and key performance indicators of USPD, and the latest spatial optical coupling experiment results of the USPD are also given. The design principle of the USPD device is to utilize Si multiplication layer of the Si SPAD as a multiplication layer instead of InP in conventional InGaAs-SPAD. The Si-SPAD has a much lower dark count rate and afterpulsing effect because of high-quality material of Si. Such a characteristic design of USPD can suppress the afterpulsing probability to the same level as that of the Si-SPAD and enables it to operate in the free-running regime without sacrificing photon detection efficiency. For the same reason, the dark count rate (DCR) of USPD is also very low. The operating mechanism of USPD is to convert the infrared photons into near-infrared or visible photons and the emitted near-infrared photons can be detected by a Si SPAD, which provides us with a new idea for single photon detection.