Disorder effect on the localization/delocalization in incommensurate potential

TL;DR

This paper investigates how incommensurate and random potentials influence electron localization in a 2D symplectic model, revealing a transition from anisotropic metallic states to localized states as disorder increases.

Contribution

It provides new insights into the disorder-induced localization transition in systems with incommensurate potentials, highlighting anisotropic metallic states and their eventual localization.

Findings

Incommensurate potential causes wavefunctions localized along the IC wavevector.

Disorder transforms these states into anisotropic metallic states.

At critical disorder strength, states become localized in both directions.

Abstract

The interplay between incommensurate (IC) and random potentials is studied in a two-dimensional symplectic model with the focus on localization/delocalization problem. With the IC potential only, there appear wavefunctions localized along the IC wavevector while extended perpendicular to it. Once the disorder potential is introduced, these turn into two-dimensional anisotropic metallic states beyond the scale of the elastic mean free path, and eventually becomes localized in both directions at a critical strength of the disorder. Implications of these results to the experimental observation of the IC-induced localization is discussed.