Towards interpreting the thermally activated $\beta$ dynamics in metallic glass with the structural constraint neural network

Abstract

Unraveling the structural factors influencing the dynamics of amorphous solids is crucial. While deep learning aids in navigating these complexities, transparency issues persist. Inspired by the successful application of prototype neural networks in the field of image analysis, this study introduces a new machine-learning approach to tackle the interpretability challenges faced in glassy research. Distinguishing from traditional machine learning models that only predict dynamics from the structural input, the adapted neural network additionally tries to learn structural prototypes under various dynamic patterns in the training phase. Such learned structural constraints can serve as a breakthrough in explaining how structural differences impact dynamics. We further use the proposed model to explore the correlation between the local structure and activation energy in the CuZr metallic glass. Building upon this interpretable model, we demonstrated significant structural differences among particles with distinct activation energies. The insights gained from this analysis serve as a data-driven solution for unraveling the origins of the structural heterogeneity in amorphous alloys, offering a valuable contribution to the understanding the amorphous materials.