Structural signature and transition dynamics of Sb2Te3 melt upon fast cooling
- Fudan Univ., Shanghai (China). Shanghai Ultra-Precision Optical Manufacturing Engineering Center. Dept. of Optical Science and Engineering
- Fudan Univ., Shanghai (China). Shanghai Ultra-Precision Optical Manufacturing Engineering Center. Dept. of Optical Science and Engineering; Key Lab. for Information Science of Electromagnetic Waves, Shanghai (China)
- Huazhong Univ. of Science and Technology, Wuhan (China). School of Optical & Electronic Information
- Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy
Crystalline Sb2Te3 is widely studied due to its important applications in memory materials and topological insulators. The liquid and amorphous structures of this compound as well as the dynamics upon quenching, however, are yet to be fully understood. In this paper, we have systematically studied the dynamical properties and local structure of Sb2Te3 at different temperatures using ab initio molecular dynamics simulations. The calculated structure factors agree well with the experimental results. The atomic number density and mean-squared displacement as a function of temperature clearly indicate three states as the temperature decreases, namely, melt, undercooled liquid and glass state, respectively. By analyzing the chemical environments and bond-angle distribution functions, we demonstrate that the most probable short-range motifs in the Sb2Te3 system are defective octahedrons, and they are connected with each other via four-fold rings. Finally, this interesting structural feature may be responsible for the high fragility and easy phase transition upon glass forming that is applied in memory devices.
- Research Organization:
- Ames Lab. and Iowa State Univ., Ames, IA (United States); Fudan Univ., Shanghai (China); Huazhong Univ. of Science and Technology, Wuhan (China)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES); National Natural Science Foundation of China (NSFC); National Key R&D Plan of China
- Grant/Contract Number:
- AC02-07CH11358; 11374055; 61427815; 51772113; 2017YFB0701700
- OSTI ID:
- 1459537
- Alternate ID(s):
- OSTI ID: 1434143
- Report Number(s):
- IS-J-9684
- Journal Information:
- Physical Chemistry Chemical Physics. PCCP, Vol. 20, Issue 17; ISSN 1463-9076
- Publisher:
- Royal Society of ChemistryCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
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