Shiyu Wang

We propose a dynamic polarization control scheme for free-space continuous-variable quantum key distribution and verify its validity via simulations and an experiment performed over a 150 m free-space channel. The results indicate the capability of the scheme to effectively control the states of polarization for free-space continuous-variable quantum communication.

Large-scale and flexible deployment of quantum networks is possible with reliable free-space quantum key distribution. However, signal fading occurs in free-space channels and causes various adverse effects. Under this circumstance, phase compensation becomes a challenging task for quantum key distribution using continuous variables. Here we investigate the feasibility of implementing phase compensation via simply computing the correlation between transmitted and received data. Demonstration and performance analysis are conducted with real transmittance of a 150-m free-space fading channel; results indicate the applicability of this compensation scheme to free-space quantum communication systems.