Measuring and engineering entropy and spin squeezing in weakly linked Bose-Einstein condensates

TL;DR

This paper introduces a method to measure and control entropy and spin squeezing in weakly linked Bose-Einstein condensates, enabling better understanding and potential enhancement of quantum entanglement and metrological precision.

Contribution

The authors propose a feasible measurement technique for local entropy and spin squeezing in optical lattices, advancing the analysis of entanglement and quantum correlations in such systems.

Findings

Feasible measurement of non-nearest-neighbour coherences

Controlled atom tunneling can improve spin squeezing

Method enables local entropy and entanglement detection

Abstract

We propose a method to infer the single-particle entropy of bosonic atoms in an optical lattice and to study the local evolution of entropy, spin squeezing, and entropic inequalities for entanglement detection in such systems. This method is based on experimentally feasible measurements of non-nearest-neighbour coherences. We study a specific example of dynamically controlling atom tunneling between selected sites and show that this could potentially also improve the metrologically relevant spin squeezing.