title: Electronic excitation induced amorphization in titanate pyrochlores: an ab initio molecular dynamics study.
abstract: The response of titanate pyrochlores (A2Ti2O7, A = Y, Gd and Sm) to electronic excitation is investigated utilizing an ab initio molecular dynamics method. All the titanate pyrochlores are found to undergo a crystalline-to-amorphous structural transition under a low concentration of electronic excitations. The transition temperature at which structural amorphization starts to occur depends on the concentration of electronic excitations. During the structural transition, O2-like molecules are formed, and this anion disorder further drives cation disorder that leads to an amorphous state. This study provides new insights into the mechanisms of amorphization in titanate pyrochlores under laser, electron and ion irradiations.
authors: School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054, China.
authors: H Y
authors: HY
authors: Xiao
authors: 1] Department of Materials Science &Engineering, University of Tennessee, Knoxville, TN 37996, USA [2] Materials Science &Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors: W J
authors: WJ
authors: Weber
authors: Materials Science &Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors: Y
authors: Y
authors: Zhang
authors: 1] School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054, China [2] Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, China.
authors: X T
authors: XT
authors: Zu
authors: School of Material Science and Engineering, University of New South Wales, Sydney, 2052, Australia.
authors: S
authors: S
authors: Li