Non-Gaussian approach: Withstanding loss and noise of multi-scattering underwater channel for continuous-variable quantum teleportation

Underwater quantum communication plays a crucial role in ensuring secure data transmission and extensible quantum networks in underwater environments. However, the implementation of such applications encounters challenges due to the light attenuation caused by the complicated natural seawater. This paper focuses on employing a model based on seawater chlorophyll-a concentration to characterize the absorption and scattering of light through quantum channels. We propose a multi-scattering random channel model, which demonstrates characteristics of the excess noise in different propagation directions of communication links. Furthermore, we consider the fidelity of a continuous-variable quantum teleportation through seawater channel. To enhance transmission performance, non-Gaussian operations have been conducted. Numerical simulations show that incorporating non-Gaussian operations enables the protocol to achieve higher fidelity transmission or lower fidelity fading rates over longer transmission distances.