# Experimental implementation of bias-free quantum random number generator based on vacuum fluctuation

## TL;DR

This paper reports the experimental development of a bias-free quantum random number generator that uses vacuum fluctuations and real-time randomness extraction, improving the quality and reliability of quantum randomness sources.

## Contribution

The study introduces an innovative phase modulation scheme to reduce device deviations and employs real-time extraction to produce unbiased, uniform random numbers from quantum vacuum fluctuations.

## Key findings

- Successfully demonstrated bias-free quantum random number generation
- Implemented real-time randomness extraction for improved output quality
- Achieved unbiased results despite device imperfections

## Abstract

We experimentally demonstrate a bias-free optical quantum random number generator with real-time randomness extraction to directly output uniform distributed random numbers by measuring the vacuum fluctuation of quantum state. A phase modulator is utilized in the scheme to effectively reduce the influence of deviations between two arms of the generator caused by the imperfect practical devices, which is an innovative solution in the field of quantum random number generator. In the case where the feedback modulation frequency is much faster than the phase jitter, an unbiased result can be obtained by an additional subtraction between the compensation signal and its average value to eliminate residual deviation. A following randomness extractor is applied to eliminate the influence of residual side information introduced by the imperfect devices in practical system.