Exploring canyons in glassy energy landscapes using metadynamics.

Area of Science:

• Materials Science
• Computational Physics
• Statistical Mechanics

Background:

• The physical properties of glass-forming systems are fundamentally governed by the low-energy configurations within their complex potential energy landscapes.
• Understanding these landscapes is crucial for predicting material behavior, particularly near phase transitions like jamming or glass formation.

Purpose of the Study:

• To develop and validate a modified metadynamics algorithm for efficient exploration of high-dimensional potential energy landscapes.
• To investigate the structure of low-energy regions in model glass-forming systems, including foams, hard sphere fluids, and the Kob-Andersen model.

Main Methods:

• Implementation of a modified metadynamics algorithm designed for enhanced sampling of potential energy landscapes.
• Application of the algorithm to model systems: a foam, hard sphere fluids, and the Kob-Andersen glass model.
• Analysis of the identified landscape features, specifically 'canyons' and associated energy minima.

Main Results:

• The algorithm successfully identified and navigated meandering canyons within the energy landscapes of the model systems.
• In hard sphere fluids, continuous fluid configurations were found across canyon floors up to high densities, surpassing the jamming transition.
• For the Kob-Andersen glass, the method efficiently sampled low-energy states, reaching energies near the theoretical Kauzmann limit.

Conclusions:

• The modified metadynamics approach provides an efficient means to explore complex energy landscapes relevant to glass-forming systems.
• The identified canyon structures offer new insights into the mechanisms governing fluid behavior and glass transitions.
• This computational technique facilitates the study of low-energy states in materials science with reduced computational cost.