title: Mechanisms of Nanoglass Ultrastability.
abstract: The origin of the astonishing properties of recently discovered ultrastable nanoglasses is presently not well understood. Nanoglasses appear to exhibit density variations not common in bulk glasses and differ significantly in thermal, magnetic, biocompatible, and mechanic properties from the bulk materials of the same composition. Here, we investigate a generic model system that permits modeling of both the physical vapor deposition process (PVD) of the nanoparticles and their consolidation into a nanoglass. We performed molecular dynamics simulations to investigate the PVD process generating nanometer-sized noncrystalline clusters and the formation of the PVD-nanoglass when these nanoclusters are consolidated. In agreement with the experiments, we find that the resulting PVD-nanoglass consists of two structural components: noncrystalline nanometer-sized cores and interfacial regions that are formed during the consolidation process. The interfacial regions were found to have an atomic structure and an internal energy that differ from the structure and internal energy of the corresponding melt-quenched glass. The resulting material represents a noncrystalline state that differs from a bulk glass with the same chemical composition and a glass obtained from nanoparticles derived from the bulk glass.
authors: Institute of Nanotechnology, Karlsruhe Institute of Technology , 76344 Eggenstein-Leopoldshafen, Germany.
authors: Denis
authors: D
authors: Danilov
authors: Institute of Nanotechnology, Karlsruhe Institute of Technology , 76344 Eggenstein-Leopoldshafen, Germany.|KIT-TUD Joint Research Laboratory Nanomaterials, TU Darmstadt , 64287 Darmstadt, Germany.
authors: Horst
authors: H
authors: Hahn
authors: Institute of Nanotechnology, Karlsruhe Institute of Technology , 76344 Eggenstein-Leopoldshafen, Germany.|Institute of Nanoscience, Nanjing University of Science and Technology , 210094 Nanjing, China.
authors: Herbert
authors: H
authors: Gleiter
authors: Institute of Nanotechnology, Karlsruhe Institute of Technology , 76344 Eggenstein-Leopoldshafen, Germany.
authors: Wolfgang
authors: W
authors: Wenzel
keywords: molecular dynamics simulations; nanoglasses; physical vapor deposition; ultrastable glasses