title: Structural phase transitions of (Bi1-xSbx)2(Te1-ySey)3compounds under high pressure and the influence of the atomic radius on the compression processes of tetradymites.
abstract: Recently, A2B3-type tetradymites have developed into a hot topic in physical and material research fields, where the A and B atoms represent V and VI group elements, respectively. In this study, in situ angle-dispersive X-ray diffraction measurements were performed on Bi2Te2Se, BiSbTeSe2, and Sb2Te2Se tetradymites under high pressure. Bi2Te2Se transforms from a layered rhombohedral structure (phase I) into 7-fold monoclinic (phase II) and body-centered tetragonal (phase IV) structures at about 8.0 and 14.3 GPa, respectively, without an 8-fold monoclinic structure (phase III) similar to that in Bi2Te3. Thus, the compression behavior of Bi2Te2Se is the same as that of Bi2Se3, which could also be obtained from first-principles calculations and in situ high-pressure electrical resistance measurements. Under high pressure, BiSbTeSe2and Sb2Te2Se undergo similar structural phase transitions to Bi2Te2Se, which indicates that the compression process of tellurides can be modulated by doping Se in Te sites. According to these high-pressure investigations of A2B3-type tetradymites, the decrease of the B-site atomic radius shrinks the stable pressure range of phase III and expands that of phase II, whereas the decrease of the A-site atomic radius induces a different effect, i.e. expanding the stable pressure range of phase III and shrinking that of phase II. The influence of the atomic radius on the compression process of tetradymites is closely related to the chemical composition and the atom arrangement in the quintuple layer.
authors.affiliation: Department of Physics, Harbin Institute of Technology, Harbin 150080, China. liuzhiguo@hit.edu.cn and Natural Science Research Center, Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150080, China. zhaojinggeng@163.com.
authors.forename: Jinggeng
authors.identifier: http://orcid.org/0000-0002-2895-1575
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China.
authors.forename: Zhenhai
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China and Department of Geological Sciences, Stanford University, Stanford, CA 94305, USA.
authors.forename: Qingyang
authors.initials: Q
authors.lastname: Hu
authors.affiliation: Department of Physics, Harbin Institute of Technology, Harbin 150080, China. liuzhiguo@hit.edu.cn.
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973, USA.
authors.forename: John
authors.initials: J
authors.lastname: Schneeloch
authors.affiliation: Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China.
authors.forename: Chunyu
authors.initials: C
authors.lastname: Li
authors.affiliation: Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973, USA.
authors.forename: Ruidan
authors.initials: R
authors.lastname: Zhong
authors.affiliation: Department of Physics, Harbin Institute of Technology, Harbin 150080, China. liuzhiguo@hit.edu.cn and Natural Science Research Center, Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150080, China. zhaojinggeng@163.com.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Physics, Harbin Institute of Technology, Harbin 150080, China. liuzhiguo@hit.edu.cn.
authors.forename: Zhiguo
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973, USA.
authors.forename: Genda
authors.initials: G
authors.lastname: Gu