Fractional quantum Hall physics with ultracold Rydberg gases in artificial gauge fields

TL;DR

This paper explores how Rydberg-dressed ultracold Bose gases under artificial gauge fields exhibit unique fractional quantum Hall states, including crystalline and bubble phases, due to their distinctive non-local interactions.

Contribution

It introduces the impact of Rydberg interaction characteristics on many-body ground states in FQH regimes, revealing new crystalline and bubble phases not seen in standard FQH systems.

Findings

Crystalline ground states dominate at very dilute densities.

A bubble crystal phase emerges when the particle spacing is less than the Rydberg blockade radius.

Indications of strongly correlated cluster liquids at higher filling fractions.

Abstract

We study ultracold Rydberg-dressed Bose gases subject to artificial gauge fields in the fractional quantum Hall (FQH) regime. The characteristics of the Rydberg interaction gives rise to interesting many-body ground states different from standard FQH physics in the lowest Landau level (LLL). The non-local but rapidly decreasing interaction potential favors crystalline ground states for very dilute systems. While a simple Wigner crystal becomes energetically favorable compared to the Laughlin liquid for filling fractions $\nu<1/12$, a correlated crystal of composite particles emerges already for $\nu \leq 1/6$ with a large energy gap to the simple Wigner crystal. The presence of a new length scale, the Rydberg blockade radius $a_B$, gives rise to a bubble crystal phase for $\nu\lesssim 1/4$ when the average particle distance becomes less than $a_B$, which describes the region of saturated, almost constant interaction potential. For larger fillings indications for strongly correlated cluster liquids are found.