Self-testing quantum randomness expansion on an integrated photonic chip

Gong Zhang; Ignatius William Primaatmaja; Yue Chen; Si Qi Ng; Hong Jie Ng; Marco Pistoia; Xiao Gong; Koon Tong Goh; Chao Wang; Charles Lim

arXiv · 2411.13712

Self-testing quantum randomness expansion on an integrated photonic chip

Gong Zhang·Ignatius William Primaatmaja·Yue Chen·Si Qi Ng·Hong Jie Ng·Marco Pistoia·Xiao Gong·Koon Tong Goh·Chao Wang·Charles Lim

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Abstract

The power of quantum random number generation is more than just the ability to create truly random numbers$\unicode{x2013}$it can also enable self-testing, which allows the user to verify the implementation integrity of certain critical quantum components with minimal assumptions. In this work, we develop and implement a self-testing quantum random number generator (QRNG) chipset capable of generating 15.33 Mbits of certifiable randomness in each run (an expansion rate of $5.11\times 10^{-4}$ at a repetition rate of 10 Mhz). The chip design is based on a highly loss-and-noise tolerant measurement-device-independent protocol, where random coherent states encoded using quadrature phase shift keying are used to self-test the quantum homodyne detection unit: well-known to be challenging to characterise in practice. Importantly, this proposal opens up the possibility to implement miniaturised self-testing QRNG devices at production scale using standard silicon photonics foundry platforms.

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Gong Zhang, Ignatius William Primaatmaja, Yue Chen, Si Qi Ng, Hong Jie Ng, Marco Pistoia, Xiao Gong, Koon Tong Goh, Chao Wang, Charles Lim. 2024-11-20. Self-testing quantum randomness expansion on an integrated photonic chip. https://arxiv.org/abs/2411.13712

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