Bias-Free Quantum Random Number Generator Hits 4.2 Gbps

A new quantum random number generator eliminates system bias and common mode noise, achieving high-speed, secure randomness with potential for chip integration.

Researchers have developed a bias-free, source-independent quantum random number generator (SI-QRNG) that leverages vacuum fluctuations to produce true random numbers at 4.2 gigabits per second. The scheme uses an all-optical Mach-Zehnder interferometer structure to remove bias and noise introduced by the local oscillator, with a common mode rejection ratio of 61.17 dB. By optimizing parameters, the system avoids simultaneously measuring two conjugate quadratures, enabling operation in three routines and offering insights into symmetrical versus asymmetrical quadrature measurements. Experimental results confirm the randomness passes NIST-STS tests, supporting applications in cryptography and secure communications. This approach facilitates integration into compact photonic chips, advancing practical quantum technologies.

Reference: Zheng, Z. et al., 2020. Bias-free source-independent quantum random number generator. arXiv:2007.08046v1 [quant-ph].