Driven-dissipative Rydberg blockade in optical lattices

TL;DR

This paper investigates the steady states of dissipative Rydberg gases in optical lattices, revealing a first order phase transition and a critical point, with implications for studying dissipative critical phenomena.

Contribution

It introduces a variational approach that includes long-range correlations to analyze the steady state, uncovering a phase transition and critical point in dissipative Rydberg systems.

Findings

Identifies a first order phase transition from a blockaded to a facilitation phase.

Discovers a critical point enabled by strong dephasing.

Shows good agreement with short-range models despite long-range interactions.

Abstract

While dissipative Rydberg gases exhibit unique possibilities to tune dissipation and interaction properties, very little is known about the quantum many-body physics of such long-range interacting open quantum systems. We theoretically analyze the steady state of a van der Waals interacting Rydberg gas in an optical lattice based on a variational treatment that also includes long-range correlations necessary to describe the physics of the Rydberg blockade, i.e., the inhibition of neighboring Rydberg excitations by strong interactions. In contrast to the ground state phase diagram, we find that the steady state undergoes a single first order phase transition from a blockaded Rydberg gas to a facilitation phase where the blockade is lifted. The first order line terminates in a critical point when including sufficiently strong dephasing, enabling a highly promising route to study dissipative criticality in these systems. In some regimes, we also find good quantitative agreement with effective short-range models despite the presence of the Rydberg blockade, justifying the wide use of such phenomenological descriptions in the literature.