On protocols for increasing the uniformity of random bits generated with noisy quantum computers

• Published in: The Journal of supercomputing Vol. 77; no. 8; pp. 8063 - 8081
• Main Authors: Combarro, Elías F., Carminati, Federico, Vallecorsa, Sofia, Ranilla, José, Rúa, Ignacio F.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.08.2021; Springer Nature B.V
• Subjects: Circuits; Compilers; Computer Science; Cryptography; High Performance Computing in Science and Engineering - CMMSE-2019; Interpreters; Numbers; Processor Architectures; Programming Languages; Quantum computers; Quantum computing; Random numbers; Statistical analysis; Statistical tests; Uniform distribution; Random bits; Quantum computers; Monobit test
• ISSN: 0920-8542; 1573-0484
• DOI: 10.1007/s11227-020-03574-7

Generating random numbers is important for many real-world applications, including cryptography, statistical sampling and Monte Carlo simulations. Quantum systems subject to a measurement produce random results via Born’s rule, and thus it is natural to study the possibility of using such systems in order to generate high-quality random numbers. However, current quantum devices are subject to errors and noise, which can make the output bits deviate from the uniform distribution. In this work, we propose and analyse two protocols that can be used to increase the uniformity of the bits obtained when running a circuit with a Hadamard gate and a measurement in a noisy quantum computer. These protocols may be used prior to other standard processes, such as randomness amplification. We conduct experiments on both a quantum simulator and a real quantum computer, obtaining results that suggest that these protocols are useful to improve the probability of the generated bits passing statistical tests for uniformity.