Mesoscopic fluctuations of the Density of States and Conductivity in the middle of the band of Disordered Lattices

TL;DR

This paper investigates mesoscopic fluctuations in the density of states and conductivity of disordered 2D and 3D lattices, highlighting the effects of impurity correlations and nesting at half filling.

Contribution

It introduces a detailed analysis of level correlations and their impact on conductivity fluctuations in disordered lattices at half filling.

Findings

Level correlations above and below the Fermi surface are significant.

Nesting enhances correlations and fluctuations at half filling.

Bragg reflections increase static conductivity fluctuations.

Abstract

The mesoscopic fluctuations of the Density of electronic States (DoS) and of the conductivity of two- and three- dimensional lattices with randomly distributed substitutional impurities are studied. Correlations of the levels lying above (or below) the Fermi surface, in addition to the correlations of the levels lying on opposite sides of the Fermi surface, take place at half filling due to nesting. The Bragg reflections mediate to increase static fluctuations of the conductivity in the middle of the band which change the distribution function of the conductivity at half- filling.