Semi-Device-Independent Quantum Random Number Generator Resistant to General Attacks

TL;DR

This paper introduces a semi-device-independent quantum random number generator that resists general attacks, operates efficiently with finite-size effects, and requires minimal device characterization, making it practical and secure.

Contribution

It proposes a novel semi-DI QRNG protocol resistant to general attacks, utilizing the Kato inequality and continuous-variable systems to enhance security and efficiency.

Findings

Achieves a net randomness generation rate of 1.165 Mbps.

Operates at 100 MHz with high security against general attacks.

Requires minimal device characterization, simplifying practical implementation.

Abstract

Quantum random number generators (QRNGs) produce true random numbers based on the inherent randomness of quantum theory, rendering them a foundational segment of quantum cryptography. Distinguished from trusted-device QRNGs whose security depends on characterized devices, semi-device-independent (semi-DI) QRNGs permit partial devices to be defective or even maliciously manipulated, which achieves a good trade-off between generation rate and security. In this paper, we propose a semi-DI QRNG that resists general attacks while accounting for finite-size effects. The protocol requires no rigorous characterization of the source and measurement devices other than limiting the energy of the emitted states, significantly reducing the demands on practical QRNG systems. Leveraging the tight Kato inequality for correlated variables, we show that our protocol generates more randomness than it consumes. Furthermore, we demonstrate the scheme on a continuous-variable system with ternary inputs of states. Heterodyne detection is employed to enable phase compensation through data postprocessing, alleviating the stringent requirement on system stability. The system operates at 100 MHz, achieving a net random number generation rate of 1.165 Mbps at 5.3x10^9 rounds. Our work offers a promising approach to achieve both the robust security and high generation rate with a simple experimental setup.