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arXiv · 2105.01858

Performance Analysis of Free-space Quantum Key Distribution Using Multiple Spatial Modes

Wenhua He·Saikat Guha·Jeffrey H. Shapiro·Boulat A. Bash
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Abstract

In the diffraction-limited near-field propagation regime, free-space optical quantum key distribution (QKD) systems can employ multiple spatial modes to improve their key rate. Here, we analyze QKD using the non-orthogonal flat-top focused beams. Although they suffer from a rate penalty, their ease of implementation makes them an attractive alternative to the well-studied orthonormal Laguerre-Gauss (LG) modes. Indeed, in the presence of turbulence, the non-orthogonal modes may achieve higher QKD rate than the LG modes.

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Wenhua He, Saikat Guha, Jeffrey H. Shapiro, Boulat A. Bash. 2021-05-05. Performance Analysis of Free-space Quantum Key Distribution Using Multiple Spatial Modes. https://doi.org/10.1364/oe.426556

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