2022/05/19 by Charles K. C. Lieou, Lieou, Charles K. C., T. Egami +1
Materials Science · Physics and Astronomy · Medicine · #Material Dynamics and Properties #Theoretical and Computational Physics #Biofield Effects and Biophysics
paper · pdf · doi:10.48550/arxiv.2205.09309
Slow relaxation and plastic deformation in disordered materials such as metallic glasses and supercooled liquids occur at dynamical heterogeneities, or neighboring particles that rearrange in a correlated, cooperative manner. Dynamical heterogeneities have historically been described by a four-point, time-dependent density correlation function χ4 (r, t). In this paper, we posit that χ4 (r, t) contains essentially the same information about medium-range order as the Van Hove correlation function G(r, t). In other words, medium-range order is the origin of spatially correlated regions of cooperative particle motion. The Van Hove function is the preferred tool for describing dynamical heterogeneities than the four-point function, for which the physical meaning is less transparent.