Extended Data Fig. 9: Performance of the monocrystalline GaAs photodetector.

a, Photograph of the single-crystalline GaAs solar cell. b, Photo and dark current density curves of the GaAs solar cell. c, EQE of the GaAs solar cell. d, Shunting resistance of the GaAs solar cell. e, DCR collected for the GaAs detector for 60 s measured at zero bias. f, Output of the GaAs detector measured at zero bias under incident light pulse with photon numbers up to 260,383. The light source for the photon-counting performance measurement is a 630-nm picosecond pulse laser from Horiba.