Noise correlation and success probability in coherent Ising machines

TL;DR

This paper investigates how noise correlations affect the success probability of coherent Ising machines, finding that normalized correlation is a better predictor than entanglement or quantum discord.

Contribution

It provides a comparative analysis of noise correlations and success probabilities in different CIM architectures, highlighting the importance of normalized correlation.

Findings

Success probability correlates more with normalized correlation than entanglement.

Quantum discord and entanglement are less predictive of success.

Numerical simulations validate the relationship between noise correlation and success rate.

Abstract

We compared the noise correlation and the success probability of coherent Ising machines (CIMs) with optical delay-line, measurement feedback, and mean-field couplings. We theoretically studied three metrics for the noise correlations in these CIMs: quantum entanglement, quantum discord, and normalized correlation of canonical coordinates. The success probability was obtained through numerical simulations of truncated stochastic differential equations based on the Wigner distribution function. The results indicate that the success probability is more directly related to the normalized correlation function rather than entanglement or quantum discord.