1998/07/24 by Ryoichi Yamamoto, Ryōichi Yamamoto, Akira Ōnuki +1 · 5 citations
Chemistry · Engineering · Materials Science · Physics and Astronomy · #Adsorption, diffusion, and thermodynamic properties of materials #Chemical physics #Diffusion #Material Dynamics and Properties #Materials science #Phase Equilibria and Thermodynamics #Physics #Statistical physics #Supercooling #Thermodynamics #cond-mat.dis-nn #cond-mat.soft
paper · pdf · doi:10.1103/physrevlett.81.4915
4 pages, 5 figures
arxiv created 1998/07/24 · openalex publication_date 1998/11/30 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The diffusivity of tagged particles is demonstrated to be heterogeneous on time scales comparable to or less than the stress relaxation time \ensuremath≅\ensuremathτ_\ensuremathα in a highly supercooled model liquid. The particle motions in the relatively active regions dominantly contribute to the mean square displacement, giving rise to a diffusion constant larger than the Stokes-Einstein value. The van Hove self-correlation function Gs(r,t) is shown to have a large r tail which can be scaled in terms of r/t1/2 for t\ensuremath\lesssim3\ensuremathτ_\ensuremathα. Its presence indicates heterogeneous diffusion in the active regions. However, the diffusion process becomes homogeneous on time scales longer than the life time of the heterogeneity structure (\ensuremath∼3\ensuremathτ_\ensuremathα).