International Conference on Computer Communication and Network Security (CCNS)

Dynamic polarization control optimization algorithm for quantum system in atmospheric channels

Jianmin Yi, Ying Guo

Published Aug 22, 2024• 0 citations

Abstract

Using time and polarization multiplexing technology for transmission can reduce the interference of free space light on quantum signals. However, because of the presence of the free space channel, during light propagation, the polarization of light undergoes random fluctuations, causing substantial light leakage during direct polarization demultiplexing at the receiver, which can overpower the quantum signal. In this paper, we present an enhanced polarization control strategy leveraging a sophisticated algorithm, improving upon an existing dynamic polarization control approach. Through simulations, our proposal shows promising performance improvements. Our work focuses on the optimization of the control algorithm within the context of the previous dynamic polarization control strategy. After identifying limitations and issues in the original algorithm, we implemented a new optimization algorithm to address these problems. Simulations indicate that our optimized algorithm effectively reduces light leakage and provides fast and accurate response to changes in the polarization state of light.

DOI: 10.1117/12.3038154

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