Shortcuts to Analog Preparation of Non-Equilibrium Quantum Lakes

TL;DR

This paper demonstrates that external driving and counterdiabatic techniques can significantly speed up the preparation of non-equilibrium quantum states, called lakes, in quantum simulation, with practical applications in Rydberg systems.

Contribution

It introduces a method to accelerate quantum lake preparation using counterdiabatic driving, extending beyond ground state targeting to non-equilibrium states.

Findings

Accelerated quantum lake preparation by nearly an order of magnitude.

Counterdiabatic driving effectively targets non-equilibrium lakes.

Experimental drive sequences are feasible for Rydberg quantum systems.

Abstract

The dynamical preparation of exotic many-body quantum states is a persistent goal of analog quantum simulation, often limited by experimental coherence times. Recently, it was shown that fast, non-adiabatic Hamiltonian parameter sweeps can create finite-size ``lakes'' of quantum order in certain settings, independent of what is present in the ground state phase diagram. Here, we show that going further out of equilibrium via external driving can substantially accelerate the preparation of these quantum lakes. Concretely, when lakes can be prepared, existing counterdiabatic driving techniques -- originally designed to target the ground state -- instead naturally target the lakes state. We demonstrate this both for an illustrative single qutrit and a model of a $\mathbb{Z}_2$ Rydberg quantum spin liquid. In the latter case, we construct experimental drive sequences that accelerate preparation by almost an order of magnitude at fixed laser power. We conclude by using a Landau-Ginzburg model to provide a semi-classical picture for how our method accelerates state preparation.