English

Wave vector dependence of the dynamics in supercooled metallic liquids

Soft Condensed Matter 2020-08-31 v2 Disordered Systems and Neural Networks

Abstract

We present a detailed investigation of the wave vector dependence of collective atomic motion in Au49Cu26.9Si16.3Ag5.5Pd2.3 and Pd42.5Cu27Ni9.5P21 supercooled liquids close to the glass transition temperature. Using x-ray photon correlation spectroscopy in a precedent uncovered spatial range of only few interatomic distances, we show that the microscopic structural relaxation process follows in phase the structure with a marked slowing down at the main average inter-particle distance. This behavior is accompanied by dramatic changes in the shape of the intermediate scattering functions which suggest the presence of large dynamical heterogeneities at length-scales corresponding to few particle diameters. A ballistic-like mechanism of particle motion seems to govern the structural relaxation of the two systems in the highly viscous phase, likely associated to hopping of caged particles in agreement with theoretical studies.

Keywords

Cite

@article{arxiv.2003.02071,
  title  = {Wave vector dependence of the dynamics in supercooled metallic liquids},
  author = {B. Ruta and S. Hechler and N. Neuber and D. Orsi and L. Cristofolini and O. Gross and B. Bochtler and M. Frey and A. Kuball and S. S. Riegler and M. Stolpe and Z. Evenson and C. Gutt and F. Westermeier and R. Busch and I. Gallino},
  journal= {arXiv preprint arXiv:2003.02071},
  year   = {2020}
}