A semi-quantitative scattering theory of amorphous materials

TL;DR

This paper presents a semi-quantitative scattering theory for amorphous materials, linking topological disorder to local strains and rotations, and relates electronic properties to disorder characteristics with validation from simulations and experiments.

Contribution

It introduces a novel semi-quantitative framework connecting topological disorder in amorphous solids to electronic localization and band tail behavior.

Findings

Localization criterion based on local strains and rotations

Relation between mobility edges and disorder potential

Decay rate dependence on temperature and static disorder

Abstract

It is argued that topological disorder in amorphous solids can be described by local strains related to local reference crystals and local rotations. An intuitive localization criterion is formulated from this point of view. The Inverse Participation Ratio and the location of mobility edges in band tails is directly related to the character of the disorder potential in amorphous solid, the coordination number, the transition integral and the nodes of wave functions of the corresponding reference crystal. The dependence of the decay rate of band tails on temperature and static disorder are derived. \textit{Ab initio} simulations on a-Si and experiments on a-Si:H are compared to these predictions.