title: Thermally Driven Electronic Topological Transition in FeTi.
abstract: Ab initio molecular dynamics, supported by inelastic neutron scattering and nuclear resonant inelastic x-ray scattering, showed an anomalous thermal softening of the M_{5}^{-} phonon mode in B2-ordered FeTi that could not be explained by phonon-phonon interactions or electron-phonon interactions calculated at low temperatures. A computational investigation showed that the Fermi surface undergoes a novel thermally driven electronic topological transition, in which new features of the Fermi surface arise at elevated temperatures. The thermally induced electronic topological transition causes an increased electronic screening for the atom displacements in the M_{5}^{-} phonon mode and an adiabatic electron-phonon interaction with an unusual temperature dependence.
authors: Applied Physics and Materials Science, California Institute of Technology, Pasadena, California 91125, USA.
authors: F C
authors: FC
authors: Yang
authors: Applied Physics and Materials Science, California Institute of Technology, Pasadena, California 91125, USA.|The Datum Institute, Beaverton, Oregon 97005, USA.
authors: J A
authors: JA
authors: Muñoz
authors: Applied Physics and Materials Science, California Institute of Technology, Pasadena, California 91125, USA.
authors: O
authors: O
authors: Hellman
authors: Applied Physics and Materials Science, California Institute of Technology, Pasadena, California 91125, USA.
authors: L
authors: L
authors: Mauger
authors: Applied Physics and Materials Science, California Institute of Technology, Pasadena, California 91125, USA.|Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433, USA.
authors: M S
authors: MS
authors: Lucas
authors: Applied Physics and Materials Science, California Institute of Technology, Pasadena, California 91125, USA.
authors: S J
authors: SJ
authors: Tracy
authors: Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors: M B
authors: MB
authors: Stone
authors: Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors: D L
authors: DL
authors: Abernathy
authors: HPCAT, Geophysical Laboratory, Carnegie Institution of Washington, Argonne, Illinois 60439, USA.
authors: Yuming
authors: Y
authors: Xiao
authors: Applied Physics and Materials Science, California Institute of Technology, Pasadena, California 91125, USA.
authors: B
authors: B
authors: Fultz