Disorder-induced liquid-solid phase coexistence in 2D electron systems

TL;DR

This paper explains the observed liquid-solid phase coexistence in 2D electron systems near quantum melting, showing that short-range disorder fluctuations induce coexistence without density differences and stabilize the Wigner Crystal phase.

Contribution

It demonstrates that short-range disorder fluctuations can cause phase coexistence without density differences and stabilize the Wigner Crystal, aligning with experimental observations.

Findings

Phase coexistence occurs without density difference due to short-range disorder.

Disorder stabilizes the Wigner Crystal at higher densities.

Results align with recent imaging experiments.

Abstract

Recent imaging experiments show a surprisingly robust regime of liquid-solid phase coexistence in a 2D electron system near the quantum melting/freezing transition, with the two phases mixed in mesoscopic domains. Strikingly, the experiments find no noticeable difference in electron density between the liquid and solid domains, which is at odds with both microemulsion scenarios and scenarios in which phase coexistence is driven by fluctuations of a long-ranged disorder potential. Here, we show that such phase coexistence without density difference can be induced by random fluctuations of a short-ranged disorder potential. We further show that disorder tends to stabilize the Wigner Crystal phase to higher densities, which is also consistent with the experiments.