Quantum control of spin-correlations in ultracold lattice gases

TL;DR

This paper presents a method to engineer non-classical spin correlations in ultracold lattice gases using quantum non-demolition measurement and feedback, enabling on-demand entanglement and specific correlation decay profiles.

Contribution

It introduces a novel approach combining QND measurement and feedback to control spin correlations in ultracold gases, which was not previously demonstrated.

Findings

Successfully prepared non-classical spin-correlation functions.

Achieved on-demand exponential and algebraic decay of correlations.

Generated a certain degree of multi-partite entanglement.

Abstract

We demonstrate that it is possible to prepare a lattice gas of ultracold atoms with a desired non-classical spin-correlation function using atom-light interaction of the kind routinely employed in quantum spin polarization spectroscopy. Our method is based on quantum non-demolition (QND) measurement and feedback, and allows in particular to create on demand exponentially or algebraically decaying correlations, as well as a certain degree of multi-partite entanglement.