%0 Journal Article
%T Unraveling a novel ferroelectric GeSe phase and its transformation into a topological crystalline insulator under high pressure
%J -
%D 2018
%R https://doi.org/10.1038/s41427-018-0081-y
%X Germanium selenide is a promising material for electronic, photovoltaic, and thermoelectric applications; however, structural phase transitions of GeSe under pressure are controversial. Combining evolutionary algorithms, density functional theory, tight-binding method, and laser-heated diamond anvil cell experiments, pressure-induced phase transitions of GeSe are thoroughly investigated. Two novel intermediate phases are predicted to exist in between the well-known ¦Á-GeSe and the recently discovered ¦Â-GeSe under high pressure. ¦Á-GeSe is found to transform into a rhombohedral crystal structure with a space group of R3m at a low hydrostatic pressure. The R3m phase of GeSe exhibits robust ferroelectricity analogous to GeTe. By further increasing the pressure to approximately 6£¿GPa, the R3m phase is predicted to transform into a rock-salt structure, becoming a 3D topological crystalline insulator with an inverted band structure. The newly discovered GeSe high-pressure phases greatly enrich our knowledge of IV¨CVI compounds
%U https://www.nature.com/articles/s41427-018-0081-y