Effect of short-ranged spatial correlations on the Anderson localization of phonons in mass-disordered systems

TL;DR

This paper studies how short-range spatial correlations in mass-disordered systems influence phonon localization, revealing that such correlations can induce a transition from localized to delocalized vibrational modes.

Contribution

It introduces a numerical analysis using TMDCA to show how pairwise correlations in disorder affect Anderson localization of phonons in three dimensions.

Findings

Correlated disorder reduces phonon localization.

A correlation-driven localization-delocalization transition occurs.

Increasing correlation strength can delocalize vibrational modes.

Abstract

We investigate the effect of spatially correlated disorder on the Anderson transition of phonons in three dimensions using a Greens function based approach, namely, the typical medium dynamical cluster approximation (TMDCA), in mass-disordered systems. We numerically demonstrate that correlated disorder with pairwise correlations mitigates the localization of the vibrational modes. A correlation driven localization-delocalization transition can emerge in a three-dimensional disordered system with an increase in the strength of correlations.