Abstract
Ab initio molecular dynamics, supported by inelastic neutron scattering and nuclear resonant inelastic x-ray scattering, showed an anomalous thermal softening of the M5- 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 M5- phonon mode and an adiabatic electron-phonon interaction with an unusual temperature dependence.
| Original language | English |
|---|---|
| Article number | 076402 |
| Journal | Physical Review Letters |
| Volume | 117 |
| Issue number | 7 |
| DOIs | |
| State | Published - Aug 8 2016 |
Funding
This work was supported by the Department of Energy through the Basic Energy Sciences Grant No. DE-FG02-03ER46055. The portions of this work conducted at Oak Ridge National Laboratory were supported by the Scientific User Facilities Division and by the Division of Materials Sciences and Engineering, Office of Basic Energy Sciences, DOE. Portions of this work were performed at HPCAT (Sector 16), Advanced Photon Source (APS), Argonne National Laboratory. HPCAT is supported by CIW, CDAC, UNLV, and LLNL through funding from DOE-NNSA, DOE-BES, and NSF. APS is supported by DOE-BES, under Contract No. DE-AC02-06CH11357. This work benefited from danse software developed under NSF Grant No. DMR-0520547. Supercomputer resources were provided by the Swedish National Infrastructure for Computing (SNIC).