title: Laser ranging at few-photon level by photon-number-resolving detection.
abstract: Sensitive laser ranging was demonstrated at few-photon level using photon-number-resolving (PNR) detectors. The reflected photon pulses from a non-cooperation remote target were distinguished in a sunlight environment of 2.5×103  lx by setting the discrimination threshold at 5-photon level. By comparing the detected photon numbers, two remote targets with different reflection coefficients were well recognized. PNR detection facilitated remote laser ranging of few-photon sensitivity with similar capabilities of linear optical detectors. This technique avoids photon-counting saturation and is important for ultra-long distance LIDAR and 3D imaging at a few photon level.
authors: Zeyu
authors: Z
authors: Bao
authors: Yan
authors: Y
authors: Liang
authors: Zhiyuan
authors: Z
authors: Wang
authors: Zhaohui
authors: Z
authors: Li
authors: E
authors: E
authors: Wu
authors: Guang
authors: G
authors: Wu
authors: Heping
authors: H
authors: Zeng