From Classical to Quantum Glasses with Ultracold Polar Molecules

TL;DR

This paper investigates how ultracold dipolar molecules in a bilayer system can exhibit both classical and quantum glassy dynamics, with tunable frustration and observable quantum heterogeneity.

Contribution

It introduces a setup for studying quantum glassy behavior in ultracold molecules, highlighting tunable frustration and quantum features of dynamical heterogeneity.

Findings

Observation of long relaxation tails indicating glassy dynamics

Identification of quantum features in dynamical heterogeneity

Experimental order parameters for quantum glass behavior

Abstract

The dynamics of a bilayer system of ultracold dipolar molecules exhibits classical and quantum glassy behavior, characterized by long tails in the relaxation time and dynamical heterogeneity. In the proposed setup, quantum fluctuations are of the order of thermal fluctuations and the degree of frustration can tuned by the interlayer distance. We present experimental accessible order parameters based on marker molecules, distinguished by properly chosen internal levels, and find quantum features of dynamical heterogeneity.