摘要
Single-photon light detection and ranging(lidar)offers single-photon sensitivity and picosecond timing resolution,which is desirable for high-precision three-dimensional(3 D)imaging over long distances.Despite important progress,further extending the imaging range presents enormous challenges because only a few echo photons return and are mixed with strong noise.Here,we tackled these challenges by constructing a high-efficiency,low-noise coaxial single-photon lidar system and developing a long-range-tailored computational algorithm that provides high photon efficiency and good noise tolerance.Using this technique,we experimentally demonstrated active single-photon 3 D imaging at a distance of up to 45 km in an urban environment,with a low return-signal level of^1 photon per pixel.Our system is feasible for imaging at a few hundreds of kilometers by refining the setup,and thus represents a step towards low-power and high-resolution lidar over extra-long ranges.
基金
National Key Research and Development Program of China(2018YFB0504300)
National Natural Science Foundation of China(61771443)
Shanghai Municipal Science and Technology Major Project(2019SHZDZX01)
Anhui Initiative in Quantum Information Technologies
Shanghai Science and Technology Development Funds(18JC1414700)
Fundamental Research Funds for the Central Universities(WK2340000083)
Youth Innovation Promotion Association of CAS(2018492)。
