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arXiv · 1208.2891

Near-Perfect Sorting of Orbital Angular Momentum and Angular Position States of Light

Malcolm N. O'Sullivan·Mohammad Mirhosseini·Mehul Malik·Robert W. Boyd
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Abstract

We present a novel method for efficient sorting of photons prepared in states of orbital angular momentum (OAM) and angular position (ANG). A log-polar optical transform is used in combination with a holographic beam-splitting method to achieve better mode discrimination and reduced cross-talk than reported previously. Simulating this method for 7 modes, we have calculated an improved mutual information of 2.43 bits/photon and 2.29 bits/photon for OAM and ANG modes respectively. In addition, we present preliminary results from an experimental implementation of this technique. This method is expected to have important applications for high-dimensional quantum key distribution systems.

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Malcolm N. O'Sullivan, Mohammad Mirhosseini, Mehul Malik, Robert W. Boyd. 2012-08-14. Near-Perfect Sorting of Orbital Angular Momentum and Angular Position States of Light. https://doi.org/10.1364/oe.20.024444

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