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arXiv · 2107.07654

Fibre polarization state compensation in entanglement-based quantum key distribution

Yicheng Shi·Hou Shun Poh·Alexander Ling·Christian Kurtsiefer
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Abstract

Quantum Key Distribution (QKD) using polarisation encoding can be hard to implement over deployed telecom fibres because the routing geometry and the birefringence of the fibre link can alter the polarisation states of the propagating photons. These alterations cause a basis mismatch, leading to an increased Quantum Bit Error Rate (QBER). In this work we demonstrate a technique for dynamically compensating fibre-induced state alteration in a QKD system over deployed fibre. This compensation scheme includes a feedback loop that minimizes the QBER using a stochastic optimization algorithm.

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Yicheng Shi, Hou Shun Poh, Alexander Ling, Christian Kurtsiefer. 2021-07-16. Fibre polarization state compensation in entanglement-based quantum key distribution. https://doi.org/10.1364/oe.437896

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