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arXiv · 1711.10294

Experimental nonlocality-based randomness generation with non-projective measurements

S. Gómez·A. Mattar·E. S. Gómez·D. Cavalcanti·O. Jiménez Farías·A. Acín·G. Lima
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Abstract

We report on an optical setup generating more than one bit of randomness from one entangled bit (i.e. a maximally entangled state of two-qubits). The amount of randomness is certified through the observation of Bell non-local correlations. To attain this result we implemented a high-purity entanglement source and a non-projective three-outcome measurement. Our implementation achieves a gain of 27$\%$ of randomness as compared with the standard methods using projective measurements. Additionally we estimate the amount of randomness certified in a one-sided device independent scenario, through the observation of EPR steering. Our results prove that non-projective quantum measurements allows extending the limits for nonlocality-based certified randomness generation using current technology.

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S. Gómez, A. Mattar, E. S. Gómez, D. Cavalcanti, O. Jiménez Farías, A. Acín, G. Lima. 2017-11-28. Experimental nonlocality-based randomness generation with non-projective measurements. https://doi.org/10.1103/physreva.97.040102

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