Quantum lidar and mimic lidar

Abstract

We describe simple quantum lidar and show it provides the best, most rapid identification of high reflectivity nearby targets. For lower reflectivities or more distant targets quantum lidar is impractical so we describe a protocol that mimics the relevant feature of quantum lidar via random intensity modulation of a classical beam. This provides a degree of covertness together with many of the other useful properties of a quantum lidar without the complication of producing quantum states and crucially, without the limit on mean photon number. Hence it is useful for identifying much lower reflectivity targets than is practical with quantum states.