Preparation of Low Entropy Correlated Many-body States via Conformal Cooling Quenches

TL;DR

This paper proposes a conformal cooling quench method to efficiently prepare low-entropy many-body states in quantum optical systems, demonstrated through simulations on spin chains and fermionic models, with potential experimental implementations.

Contribution

It introduces a novel entropy-shifting protocol called conformal cooling quench, applicable to systems with long-range interactions, to achieve low-temperature quantum states.

Findings

Moderately sized bath regions can significantly reduce entropy density.

Finite temperature simulations show the protocol exposes coherent low-temperature physics.

Implementation is feasible in optical lattices with long-range interactions.

Abstract

We analyze a method for preparing low-entropy many-body states in isolated quantum optical systems of atoms, ions and molecules. Our approach is based upon shifting entropy between different regions of a system by spatially modulating the magnitude of the effective Hamiltonian. We conduct two case studies, on a topological spin chain and the spinful fermionic Hubbard model, focusing on the key question: can a "conformal cooling quench" remove sufficient entropy within experimentally accessible timescales? Finite temperature, time-dependent matrix product state calculations reveal that even moderately sized "bath" regions can remove enough energy and entropy density to expose coherent low temperature physics. The protocol is particularly natural in systems with long-range interactions such lattice-trapped polar molecules and Rydberg dressed atoms where the magnitude of the Hamiltonian scales directly with the density. To this end, we propose a simple implementation of conformal cooling quenches in a dilutely-filled optical lattice, where signatures of quantum magnetism can be observed.