title: Pressure-induced superconductivity in the giant Rashba system BiTeI.
abstract: At ambient pressure, BiTeI exhibits a giant Rashba splitting of the bulk electronic bands. At low pressures, BiTeI undergoes a transition from trivial insulator to topological insulator. At still higher pressures, two structural transitions are known to occur. We have carried out a series of electrical resistivity and AC magnetic susceptibility measurements on BiTeI at pressure up to  ∼40 GPa in an effort to characterize the properties of the high-pressure phases. A previous calculation found that the high-pressure orthorhombic P4/nmm structure BiTeI is a metal. We find that this structure is superconducting with Tcvalues as high as 6 K. AC magnetic susceptibility measurements support the bulk nature of the superconductivity. Using electronic structure and phonon calculations, we compute Tcand find that our data is consistent with phonon-mediated superconductivity.
authors.affiliation: Department of Physics, University of Florida, Gainesville, FL 32611, United States of America.
authors.forename: D
authors.initials: D
authors.lastname: VanGennep
authors.forename: A
authors.initials: A
authors.lastname: Linscheid
authors.forename: D E
authors.initials: DE
authors.lastname: Jackson
authors.forename: S T
authors.initials: ST
authors.lastname: Weir
authors.forename: Y K
authors.initials: YK
authors.lastname: Vohra
authors.forename: H
authors.initials: H
authors.lastname: Berger
authors.forename: G R
authors.initials: GR
authors.lastname: Stewart
authors.forename: R G
authors.initials: RG
authors.lastname: Hennig
authors.forename: P J
authors.initials: PJ
authors.lastname: Hirschfeld
authors.forename: J J
authors.initials: JJ
authors.lastname: Hamlin