Damping effects and the metal-insulator transition in the two-dimensional electron gas

TL;DR

This paper investigates how damping influences the metal-insulator transition in a two-dimensional electron gas, emphasizing the role of scattering suppression in maintaining quasiparticle validity near phase transitions.

Contribution

It introduces a detailed analysis of damping effects on quasiparticles and applies these insights to explain the conductivity behavior during the metal-insulator transition.

Findings

Damping suppresses scattering amplitude near the transition.

Quasiparticle picture remains valid due to damping effects.

Conductivity behavior is elucidated in the transition region.

Abstract

The damping of single-particle degrees of freedom in strongly correlated two-dimensional Fermi systems is analyzed. Suppression of the scattering amplitude due to the damping effects is shown to play a key role in preserving the validity of the Landau-Migdal quasiparticle picture in a region of a phase transition, associated with the divergence of the quasiparticle effective mass. The results of the analysis are applied to elucidate the behavior of the conductivity $\sigma(T)$ of the two-dimensional dilute electron gas in the density region where it undergoes a metal-insulator transition.