A bias-free quantum random number generation using photon arrival time selectively

We present a high-quality, bias-free quantum random number generator (QRNG) using photon arrival time selectively in accordance with the number of photon detection events within a sampling time interval in attenuated light. It is well showed in both theoretical analysis and experiments verification that this random number production method eliminates both bias and correlation perfectly without more post processing and the random number can clearly pass the standard randomness tests. We fulfill theoretical analysis and experimental verification of the method whose rate can reach up to 45Mbps.

💡 Research Summary

The paper introduces a quantum random number generator (QRNG) that eliminates bias and autocorrelation by selectively using photon arrival times only when exactly one photon is detected within a predefined sampling window. The authors begin by highlighting the shortcomings of conventional QRNGs, which typically map raw photon arrival times or detection events directly to bits. Such approaches are vulnerable to detector inefficiencies, dead time, after‑pulsing, and multi‑photon events, all of which introduce statistical bias and temporal correlations.

The proposed method relies on attenuated laser light that follows a Poisson photon‑arrival process with mean rate λ. A fixed sampling interval T (on the order of tens of nanoseconds) is defined, and the number of detection events N in each interval is counted in real time. If N = 1, the precise arrival time t of that single photon (0 ≤ t ≤ T) is recorded; otherwise the interval is discarded. Because the conditional probability density of t given N = 1 is uniform over