Quantum crystal phase of electron liquid

TL;DR

This paper introduces a novel bosonic excitonic approach to analyze the two-dimensional electron liquid, revealing a quantum crystal phase and explaining the metal-insulator transition.

Contribution

It develops a new excitonic method for interacting electrons, demonstrating a quantum crystal phase and its implications for electron liquid behavior.

Findings

Identification of a noncompensated quantum crystal phase in 2D electron liquid

Correlation energy and susceptibility agree with previous studies

Proof of Fermi surface instability as $r_s\to 0$

Abstract

A new bosonic, excitonic method for interacting electrons is developed. For two-dimensional electron liquid, it reveals a noncompensated quantum crystal phase ranging from the high density, or vanishing Coulomb interaction, limit: $r_s=0$, to a lower density $r_s\sim 10$, where a condensation of exciton pairs and the loss of the Fermi step is possible. The correlation energy and the static susceptibility, calculated using the method, are in agreement with the independent studies. A proof of the instability of the Fermi surface in the limit $r_s\to 0$ is given. The concept of quantum crystal is capable to explain the metal-insulator transition in Si field-effect heterostructures.