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.
@article{arxiv.2105.01858,
title = {Performance Analysis of Free-space Quantum Key Distribution Using Multiple Spatial Modes},
author = {Wenhua He and Saikat Guha and Jeffrey H. Shapiro and Boulat A. Bash},
journal= {arXiv preprint arXiv:2105.01858},
year = {2021}
}
Comments
13 pages, 5 figures (if I count all the subfigures the total number is 9) submitted to Optics express