Quantum melting of two-component Rydberg crystals

TL;DR

This paper studies the quantum melting process of one-dimensional two-component Rydberg crystals, revealing step-like melting behavior influenced by quantum fluctuations and exchange interactions, with potential devil's staircase structures.

Contribution

It introduces a detailed analysis of quantum melting in two-component Rydberg crystals, highlighting the effects of laser-induced fluctuations and exchange interactions on phase transitions.

Findings

Quantum fluctuations can induce a devil's staircase structure.

Exchange interactions lead to step-like melting in small crystals.

Stable crystalline phases are identified in the classical limit.

Abstract

We investigate the quantum melting of one dimensional crystals that are realized in an atomic lattice in which ground state atoms are laser excited to two Rydberg states. We focus on a regime where both, intra- and inter-state density-density interactions as well as coherent exchange interactions contribute. We determine stable crystalline phases in the classical limit and explore their melting under quantum fluctuations introduced by the excitation laser as well as two-body exchange. We find that within a specific parameter range quantum fluctuations introduced by the laser can give rise to a devil's staircase structure which one might associate with transitions in the classical limit. The melting through exchange interactions is shown to also proceed in a step-like fashion, in case of small crystals, due to the proliferation of Rydberg spinwaves.