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Title: Energy landscape-driven non-equilibrium evolution of inherent structure in disordered material

Abstract

Complex states in glasses can be neatly expressed by the potential energy landscape (PEL). But, because PEL is highly multi-dimensional it is difficult to describe how the system moves around in PEL. We demonstrate that it is possible to predict the evolution of macroscopic state in a metallic glass, such as ageing and rejuvenation, through a set of simple equations describing excitations in the PEL. The key to this simplification is the realization that the step of activation from the initial state to the saddle point in PEL and the following step of relaxation to the final state are essentially decoupled. Furthermore, the model shows that the interplay between activation and relaxation in PEL is the key driving force that simultaneously explains both the equilibrium of supercooled liquid and the thermal hysteresis observed in experiments. It further predicts anomalous peaks in truncated thermal scanning, validated by independent molecular dynamics simulation.

Authors:
 [1];  [2];  [3]
  1. Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Mechnical Engineering
  2. Oita Univ. (Japan). Division of Natural Sciences
  3. Joint Inst. for Neutron Sciences, Knoxville, TN (United States). Shull Wollan Center; Univ. of Tennessee, Knoxville, TN (United States). Dept. of Materials Science adn Engineering and Dept. of Physics and Astronomy; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1360078
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; atomistic models; glasses

Citation Formats

Fan, Yue, Iwashita, Takuya, and Egami, Takeshi. Energy landscape-driven non-equilibrium evolution of inherent structure in disordered material. United States: N. p., 2017. Web. doi:10.1038/ncomms15417.
Fan, Yue, Iwashita, Takuya, & Egami, Takeshi. Energy landscape-driven non-equilibrium evolution of inherent structure in disordered material. United States. doi:10.1038/ncomms15417.
Fan, Yue, Iwashita, Takuya, and Egami, Takeshi. Fri . "Energy landscape-driven non-equilibrium evolution of inherent structure in disordered material". United States. doi:10.1038/ncomms15417. https://www.osti.gov/servlets/purl/1360078.
@article{osti_1360078,
title = {Energy landscape-driven non-equilibrium evolution of inherent structure in disordered material},
author = {Fan, Yue and Iwashita, Takuya and Egami, Takeshi},
abstractNote = {Complex states in glasses can be neatly expressed by the potential energy landscape (PEL). But, because PEL is highly multi-dimensional it is difficult to describe how the system moves around in PEL. We demonstrate that it is possible to predict the evolution of macroscopic state in a metallic glass, such as ageing and rejuvenation, through a set of simple equations describing excitations in the PEL. The key to this simplification is the realization that the step of activation from the initial state to the saddle point in PEL and the following step of relaxation to the final state are essentially decoupled. Furthermore, the model shows that the interplay between activation and relaxation in PEL is the key driving force that simultaneously explains both the equilibrium of supercooled liquid and the thermal hysteresis observed in experiments. It further predicts anomalous peaks in truncated thermal scanning, validated by independent molecular dynamics simulation.},
doi = {10.1038/ncomms15417},
journal = {Nature Communications},
number = ,
volume = 8,
place = {United States},
year = {Fri May 19 00:00:00 EDT 2017},
month = {Fri May 19 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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