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arXiv · 1204.5781

Influence of Atmospheric Turbulence on Optical Communications using Orbital Angular Momentum for Encoding

Mehul Malik·Malcolm O'Sullivan·Brandon Rodenburg·Mohammad Mirhosseini·Jonathan Leach·Martin P. J. Lavery·Miles J. Padgett·Robert W. Boyd
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Abstract

We describe an experimental implementation of a free-space 11-dimensional communication system using orbital angular momentum (OAM) modes. This system has a maximum measured OAM channel capacity of 2.12 bits/photon. The effects of Kolmogorov thin-phase turbulence on the OAM channel capacity are quantified. We find that increasing the turbulence leads to a degradation of the channel capacity. We are able to mitigate the effects of turbulence by increasing the spacing between detected OAM modes. This study has implications for high-dimensional quantum key distribution (QKD) systems. We describe the sort of QKD system that could be built using our current technology.

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Mehul Malik, Malcolm O'Sullivan, Brandon Rodenburg, Mohammad Mirhosseini, Jonathan Leach, Martin P. J. Lavery, Miles J. Padgett, Robert W. Boyd. 2012-04-25. Influence of Atmospheric Turbulence on Optical Communications using Orbital Angular Momentum for Encoding. https://doi.org/10.1364/oe.20.013195

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