Super-sensitivity interferometric quantum lidar with squeezed-vacuum injection

Interferometric lidar is a device to achieve high precision distance detection by phase estimation. The phase sensitivity of the traditional interferometric lidar is limited by the standard quantum limit, this affecting the precision of ranging. In order to further break the limit and improve the system precision, a scheme of super-sensitivity interferometric quantum lidar with squeezed-vacuum injection was put forward, thus phase sensitivity breaking through the standard quantum limit. And the phase sensitivity of the system was derived with Z detection, intensity difference detection and parity detection method. Then, the ascension of performance was compared and analyzed by simulation calculation. Finally, on the basis of best detection method-parity detection, a phase sensitivity model with transmission loss was establised, and the maximum transmission loss allowed by super-sensitivity was discussed.