Certified Random Number Generation using Quantum Computers

Abstract: In recent decades, quantum technologies have made significant strides toward achieving quantum utility. However, practical applications are hindered by challenges related to scaling the number of qubits and the depth of circuits. In this paper, we investigate how current quantum computers can be leveraged for practical applications, particularly in generating secure random numbers certified by Quantum Mechanics. While random numbers can be generated and certified in a device-independent manner through the violation of Bell's inequality, this method requires significant spatial separation to satisfy the no-signaling condition, making it impractical for implementation on a single quantum computer. Instead, we employ temporal correlations to generate randomness by violating the Leggett-Garg inequality, which relies on the No-Signaling in Time condition to certify randomness, thus overcoming spatial constraints. By applying this protocol to existing quantum computers, we demonstrate the feasibility of secure, semi-device-independent random number generation using low-depth circuits with single-qubit gates.