2021/03/31 by Cyrus E. Dreyer, Sinisa Coh, Massimiliano Stengel
Chemistry · Materials Science · Physics and Astronomy · #Adiabatic process #Advanced Physical and Chemical Molecular Interactions #Born approximation #Chemistry #Condensed matter physics #Density functional theory #Doping #Drude model #Electron #Electronic and Structural Properties of Oxides #Physics #Polarization (electrochemistry) #Quantum electrodynamics #Quantum mechanics #Semiconductor #Surface and Thin Film Phenomena #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevlett.128.095901
published as Phys. Rev. Lett. 128, 095901 (2022) · 6 pages, 3 figures. Supplemental material: 10 pages, 11 figures
openalex publication_date 2022/02/28 · arxiv created 2022/03/07 · arxiv updated 2022/03/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
In insulators, Born effective charges describe the electrical polarization induced by the displacement of individual atomic sublattices. Such a physical property is at first sight irrelevant for metals and doped semiconductors, where the macroscopic polarization is ill-defined. Here we show that, in clean conductors, going beyond the adiabatic approximation results in nonadiabatic Born effective charges that are well defined in the low-frequency limit. In addition, we find that the sublattice sum of the nonadiabatic Born effective charges does not vanish as it does in the insulating case, but instead is proportional to the Drude weight. We demonstrate these formal results with density functional perturbation theory calculations of Al, and electron-doped SnS2 and SrTiO3.