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arXiv · 2310.02354

Multi-Gbps quantum randomness source based on direct detection and vacuum states

Dino Solar Nikolic·Cosmo Lupo·Runjia Zhang·Tobias Rydberg·Ulrik L. Andersen·Tobias Gehring
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Abstract

Quantum random number generators (QRNGs) based on quadrature measurements of the vacuum have so far used balanced homodyne detection to obtain a source of high entropy. Here we propose a simple direct detection measurement scheme using only a laser and a photodiode that still extracts randomness from vacuum fluctuations. We prove the security of the QRNG based on a reduced set of assumptions in comparison to previous security proofs for quadrature detection as our proof does not require the laser or electronic noise to be Gaussian. Using a low-cost setup based on a vertical-cavity surface-emitting laser we experimentally implement the QRNG scheme. We propose a system characterization method, apply it to our implementation and demonstrate a real-time randomness extraction rate of 3.41 Gbit per second. The unique combination of speed, low cost, and rigorous security proof gives our QRNG design a large potential for a wide-scale usage in a variety of applications ranging from quantum key distribution to mobile applications and internet of things.

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Dino Solar Nikolic, Cosmo Lupo, Runjia Zhang, Tobias Rydberg, Ulrik L. Andersen, Tobias Gehring. 2023-10-03. Multi-Gbps quantum randomness source based on direct detection and vacuum states. https://arxiv.org/abs/2310.02354

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