PhD defence: Anomalous dynamics of disordered materials


Disordered materials refer to a category of materials that lack long-range correlations but possess local interactions. This disorder influences several physical properties of the material, including electrical conductivity, optical characteristics, and mechanical properties. The study of disordered materials is of paramount importance as many practical materials, such as plastics, glass, polymers, and certain ceramics, are categorized as such.

This dissertation employs extensive Monte Carlo (MC) simulations and statistical analysis to investigate the long-overlooked dynamical properties of disordered materials. Initially, we studied the critical dynamical behaviors of the Ising model with Glauber dynamics in two and three dimensions. Through the analysis of the mean squared displacement (MSD) and the autocorrelation function (AF) of magnetization, we found a new critical dynamic exponent and a three-stage dynamic regime. These findings are expected to promote the research on sampling of statistically uncorrelated samples and dynamic universality in phase transition systems.

Furthermore, we utilized Monte Carlo (MC) methods based on the Wooten, Winer, and Weaire (WWW) algorithm to simulate and study the structural dynamic properties of polycrystalline graphene and amorphous silicon (a-Si). These dynamic characteristics quantitatively and qualitatively established the relationship between intrinsic features in disordered materials, such as defect density, grain boundaries, size, etc., and mechanical properties (like shear modes, bulk modes). We also conducted a detailed study of the nonlinear dynamical process of domain growth in polycrystalline graphene. We believe that this research will provide guidance for the manufacturing of tunable disordered materials.

Start date and time
End date and time
Online (livestream link)
PhD candidate
Z. Liu
Anomalous dynamics of disordered materials
PhD supervisor(s)
prof. dr. G.T. Barkema
dr. D. Panja
More information
Full text via Utrecht University Repository