title: Bulk signatures of pressure-induced band inversion and topological phase transitions in Pb(1-x)Sn(x)Se.
abstract: The characteristics of topological insulators are manifested in both their surface and bulk properties, but the latter remain to be explored. Here we report bulk signatures of pressure-induced band inversion and topological phase transitions in Pb(1-x)Sn(x)Se (x=0.00, 0.15, and 0.23). The results of infrared measurements as a function of pressure indicate the closing and the reopening of the band gap as well as a maximum in the free carrier spectral weight. The enhanced density of states near the band gap in the topological phase gives rise to a steep interband absorption edge. The change of density of states also yields a maximum in the pressure dependence of the Fermi level. Thus, our conclusive results provide a consistent picture of pressure-induced topological phase transitions and highlight the bulk origin of the novel properties in topological insulators.
authors.affiliation: Photon Sciences, Brookhaven National Laboratory, Upton, New York 11973, USA.
authors.forename: Xiaoxiang
authors.initials: X
authors.lastname: Xi
authors.affiliation: Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA and Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794, USA.
authors.forename: Xu-Gang
authors.initials: XG
authors.lastname: He
authors.affiliation: Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794, USA.
authors.forename: Fen
authors.initials: F
authors.lastname: Guan
authors.affiliation: Geophysical Laboratory, Carnegie Institution of Washington, Washington DC 20015, USA.
authors.forename: Zhenxian
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
authors.forename: R D
authors.initials: RD
authors.lastname: Zhong
authors.affiliation: Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Schneeloch
authors.affiliation: Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA and School of Chemical Engineering and Environment, North University of China, Taiyuan 030051, China.
authors.forename: T S
authors.initials: TS
authors.lastname: Liu
authors.affiliation: Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
authors.forename: G D
authors.initials: GD
authors.lastname: Gu
authors.forename: X
authors.initials: X
authors.lastname: Du
authors.affiliation: Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794, USA.
authors.forename: D
authors.initials: D
authors.lastname: Xu
authors.affiliation: Department of Geosciences, Stony Brook University, Stony Brook, New York 11794, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Geosciences, Stony Brook University, Stony Brook, New York 11794, USA.
authors.forename: X G
authors.initials: XG
authors.lastname: Hong
authors.affiliation: Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Ku
authors.affiliation: Photon Sciences, Brookhaven National Laboratory, Upton, New York 11973, USA.
authors.forename: G L
authors.initials: GL
authors.lastname: Carr