Quasi-localized vibrational modes, Boson peak and sound attenuation in model mass-spring networks

TL;DR

This paper presents an algorithm to create disordered mass-spring networks that replicate glass-like vibrational properties, revealing how local elastic fluctuations influence vibrational anomalies and sound attenuation.

Contribution

The authors develop a novel algorithm to tune local elastic fluctuations in mass-spring networks, accurately reproducing glass vibrational features and their dependence on stability.

Findings

Reproduces Boson peak and quasi-localized modes in 2D networks.

Shows sound attenuation follows Rayleigh scattering and disorder regimes.

Attenuation rate increases with network stability.

Abstract

We introduce an algorithm that constructs disordered mass-spring networks whose elastic properties mimic that of glasses by tuning the fluctuations of the local elastic properties, keeping fixed connectivity and controlling the prestress. In two dimensions, the algorithm reproduces the dependence of gasses' vibrational properties, such as quasi-localised vibrational modes and Boson peak, on the degree of stability. The sound attenuation displays Rayleigh scattering and disorder-broadening regimes at different frequencies, and the attenuation rate increases with increased stability. Our results establish a strong connection between the vibrational features of disordered solids and the fluctuations of the local elastic properties and provide a new approach to investigating glasses' vibrational anomalies.