Three-dimensional single-pixel imaging using a fractal superconducting nanowire single-photon detector

Faint-light imaging plays an important role in applications including fluorescence-lifetime microscopy and remote sensing. Superconducting nanowire single-photon detectors (SNSPDs) outperform other single-photon detectors in terms of the comprehensive performances, however, large-format SNSPD imagers with many pixels remain an outstanding technological challenge. Here, as an alternative route, we use a multimode-fiber-coupled fractal SNSPD as the light-sensing element to perform three-dimensional single-pixel imaging at the wavelength of 1560 nm. We demonstrate a depth resolution of less than 6 mm with image resolution of 64 × 64. By further using a compressive-sensing scheme, the system is capable of reconstructing images with resolution of 128 × 128 and the maximum photon counts per pixel fewer than 1.