arXiv:2110.06387 · AVS Quantum Science

Quantum randomness generation via orbital angular momentum modes crosstalk in a ring-core fiber

Mujtaba Zahidy, Hamid Tebyanian, Daniele Cozzolino, Yaoxin Liu, Yunhong Ding, Toshio Morioka, Leif Katsuo Oxenløwe, Davide Bacco

Published Feb 8, 2022• 18 citations

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Abstract

Genuine random numbers can be produced beyond a shadow of doubt through the intrinsic randomness provided by quantum mechanics theories. While many degrees of freedom have been investigated for randomness generation, adequate attention has not been paid to the orbital angular momentum of light. In this work, we present a quantum random number generator based on the intrinsic randomness inherited from the superposition of orbital angular momentum modes caused by the cross talk inside a ring-core fiber. We studied two possible cases: a first one, device-dependent, where the system is trusted, and a second one, semi-device-independent, where the adversary can control the measurements. We experimentally realized the former, extracted randomness, and, after privacy amplification, we achieved a generation rate higher than 10 Mbit/s. In addition, we presented a possible realization of the semi-device-independent protocol using a newly introduced integrated silicon photonic chip. Our work can be considered as a starting point for novel investigation of quantum random number generators based on the orbital angular momentum of light.

DOI: 10.1116/5.0074253

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