Probing unitary two-time correlations in a neutral atom quantum simulator

TL;DR

This paper discusses the challenges and proposes a modified protocol for measuring two-time correlations in quantum simulators, specifically in neutral atom systems, and estimates the accuracy of these methods using Lieb-Robinson bounds.

Contribution

It introduces a modified measurement protocol for two-time correlations in neutral atom quantum simulators and rigorously estimates its accuracy using Lieb-Robinson bounds.

Findings

Proposed a modified measurement protocol for two-time correlations.

Estimated the protocol's accuracy using Lieb-Robinson bounds.

Identified parameter regimes for accurate measurements.

Abstract

Measuring unitarily-evolved quantum mechanical two-time correlations is challenging in general. In a recent paper [P.~Uhrich {\em et al.}, Phys.\ Rev.~A {\bf 96}, 022127 (2017)], a considerable simplification of this task has been pointed out to occur in spin-$1/2$ lattice models, bringing such measurements into reach of state-of-the-art or near-future quantum simulators of such models. Here we discuss the challenges of an experimental implementation of measurement schemes of two-time correlations in quantum gas microscopes or microtrap arrays. We propose a modified measurement protocol that mitigates these challenges, and we rigorously estimate the accuracy of the protocols by means of Lieb-Robinson bounds. On the basis of these bounds we identify a parameter regime in which the proposed protocols allow for accurate measurements of the desired two-time correlations.