Fig. 1. (a) Photo of Ti TES-based superconducting single-photon detector, L and W present the device length and width, CP is the overlap of contact pads. (b) TEM images of Ti TES, the periodic distribution structure is the dielectric mirror, on the left is the Nb/Ti overlapping area, on the right is the Ti active area. (c) IR image of light spot from the single-mode fiber and TES active area. (d) Measurement setup of TES-based superconducting single-photon detectors responding to an attenuated pulse signal, induced current is firstly amplified by SQUID

Fig. 2. (a) Current-voltage characteristics of TES-based superconducting single-photon detectors, (b) Joule power(P₀=I₀V₀) at 0.3R_n as a function of T_B

Fig. 3. (a) Calculated and measured τ_eff of TES-based superconducting single-photon detectors, (b) calculated C of TES-based superconducting single-photon detectors

Fig. 4. Response height histogram of TES-based superconducting single-photon detectors at 0.3R_n and 100 mK, the response height is normalized to the one responding to one 1 550 nm photon (a) No.3, (b) No.2, (c) No.1

Fig. 5. (a) Calculated and measured ΔE of TES-based superconducting single-photon detectors, (b) M²/α factor of TES-based superconducting single-photon detectors as a function of R₀/R_n

Fig. 6. (a) Calculated response curves of TES-based superconducting single-photon detectors at 0.3R_n responding to a single 1 550 nm photon, (b) calculated and measured response height of No.3 as a function of R₀/R_n responding to a single 1 550 nm photon.

Fig. 7. Calculated ΔE of TES with a dimension of 20 μm×20 μm as a function of T_C

Table 1. Parameters of TES-based superconducting single-photon detectors with different dimensions measured at 0.3R_n and 100 mK