Controlled formation of metastable germanium polymorphs

被引：53

作者：

Haberl, Bianca ^{[1
]}

Guthrie, Malcolm ^{[2
]}

Malone, Brad D. ^{[3
]}

Smith, Jesse S. ^{[4
]}

Sinogeikin, Stanislav V. ^{[4
]}

Cohen, Marvin L. ^{[5
,6
]}

Williams, James S. ^{[1
]}

Shen, Guoyin ^{[4
]}

Bradby, Jodie E. ^{[1
]}

机构：

[1] Australian Natl Univ, Res Sch Phys & Engn, Dept Elect Mat Engn, Canberra, ACT 0200, Australia

[2] Carnegie Inst Sci, Geophys Lab, Washington, DC 20015 USA

[3] Harvard Univ, Sch Engn & Appl Sci, Cambridge, MA 02138 USA

[4] Carnegie Inst Sci, Geophys Lab, High Pressure Collaborat Access Team, Argonne, IL 60439 USA

[5] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA

[6] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA

来源：

PHYSICAL REVIEW B | 2014年 / 89卷 / 14期

基金：

澳大利亚研究理事会; 美国国家科学基金会;

关键词：

INDUCED PHASE-TRANSFORMATION; HIGH-PRESSURE PHASES; CRYSTAL STRUCTURES; AMORPHOUS PHASES; SILICON; GE; SI; NANOINDENTATION; TRANSITIONS; STABILITY;

D O I：

10.1103/PhysRevB.89.144111

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The nucleation of metastable germanium polymorphs on decompression is studied using in situ synchrotron x-ray diffraction. We show that the transition pathway is critically dependent on the hydrostaticity. Quasihydrostatic conditions result in the nucleation of the rhombohedral r8 phase, followed by the cubic bc8 and hexagonal diamond phases. In contrast, the presence of shear yields the tetragonal st12 phase. Thus, targeted nucleation of a metastable polymorph is now possible. This observation has implications for the technological exploitation of Ge, but also for other tetrahedral systems.

引用

页数：6

共 50 条

[1] ANHARMONICITY AND THE EQUATION OF STATE FOR GOLD [J].