Quantum Random Number Generator with Internal Consistency Check and Public Verification

TL;DR

This paper introduces a simple, passive optical quantum random number generator that self-tests its operation and produces both private and publicly verifiable randomness, enhancing security and trustworthiness.

Contribution

It presents a novel looped beam splitter architecture with intrinsic self-testing and dual output sequences for secure and public verification of quantum randomness.

Findings

Achieves continuous validation of operation through detection-probability ratios.

Generates two independent sequences: one private and one publicly verifiable.

Maintains security while enabling external randomness verification.

Abstract

Quantum Random Number Generators provide true physical randomness based on quantum processes, essential for cryptographic and scientific applications. However, practical implementations face challenges in robustness and verifiability: ensuring that the entropy source remains secure and stable over time, and enabling independent confirmation of randomness quality without compromising security. We present a system based on a simple looped beam splitter architecture that uses only passive optical components. The device features an intrinsic self-testing mechanism derived from the stability of detection-probability ratios, allowing continuous validation of correct operation. In addition, the same physical process generates two independent random sequences with identical entropy: a private sequence, used for secure applications, and a public one, enabling external statistical verification with zero mutual information between them. This approach demonstrates that robust, self-testing, and publicly verifiable quantum randomness can be achieved with minimal optical complexity without jeopardizing security.