Effects of real environments on the performance of quantum Lidar

The effects of loss and noise (real environments) on the performance of quantum lidar with odd coherent superposition states source (OCRS) was investigeted. The general expression of conditional probabilities and parity photon counting measurement strategies were exploited to derive the mean value of the output signal and its phase sensitivity from the Mach-Zehnder interferometer (MZI). It can be found from the output signal that loss destroys the coherence and further descents the performance of lidar. The numerical calculation shows that the odd and even interference fringes emerge in the whole interference pattern, and the odd interference term which represents the coherence is extremely sensitive to particle loss. The odd coherent states quantum lidar outperforms the performance achieved by the traditional coherent states (CS) lidar only in small loss regimes. However, in the noisy environments, OCRS gives the better resolution and sensitivity than CS in the regions of κ>0.3 and κ>0.06, respectively.