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arXiv · 1608.05155

Quantum random number generation enhanced by weak-coherent states interference

T. Ferreira da Silva·G. B. Xavier·G. C. Amaral·G. P. Temporão·J. P. von der Weid
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Abstract

We propose and demonstrate a technique for quantum random number generation based on the random population of the output spatial modes of a beam splitter when both inputs are simultaneously fed with indistinguishable weak coherent states. We simulate and experimentally validate the probability of generation of random bits as a function of the average photon number per input, and compare it to the traditional approach of a single weak coherent state transmitted through a beam-splitter, showing an improvement of up to 32\%. The ensuing interference phenomenon reduces the probability of coincident counts between the detectors associated with bits 0 and 1, thus increasing the probability of occurrence of a valid output. A long bit string is assessed by a standard randomness test suite with good confidence. Our proposal can be easily implemented and opens attractive performance gains without a significant trade-off.

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T. Ferreira da Silva, G. B. Xavier, G. C. Amaral, G. P. Temporão, J. P. von der Weid. 2016-08-18. Quantum random number generation enhanced by weak-coherent states interference. https://doi.org/10.1364/oe.24.019574

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