Universal configuration for optimizing randomness generation in variational distributed quantum circuits
Phys. Rev. A 113, 032610 – Published 9 March, 2026
DOI: https://doi.org/10.1103/pwz2-yg3f
Abstract
Distributed quantum computing represents at present one of the most promising approaches to scaling quantum processors. Current implementations typically partition circuits into multiple cores, each composed of several qubits, with intercore connectivity playing a central role in ensuring scalability. Identifying the optimal configuration—defined as the arrangement that maximizes circuit Haar randomness generation with minimal depth—thus constitutes a fundamental design challenge. In this work, we demonstrate, both analytically and numerically, the existence of a universal optimal configuration for distributing single- and two-qubit gates across arbitrary intercore communication topologies in variational distributed circuits. Our proof is based on a Haar randomness measure based on Markov matrices, which quantifies the convergence rate towards the Haar measure [Y. S. Weinstein, W. G. Brown, and L. Viola, Phys. Rev. A 78, 052332 (2008)]. Finally, we validate our predictions through numerical comparisons with the well-established majorization criterion [J. Montes, F. Borondo, and G. G. Carlo, APL Quantum 2, 026104 (2025)].
