Accession Number : ADA518640


Title :   Effects of Magnetism and Doping on the Electron-Phonon Coupling in BaFe2As2


Descriptive Note : Electronic preprint


Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC


Personal Author(s) : Boeri, L ; Calandra, M ; Mazin, I I ; Dolgov, O V ; Mauri, F


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a518640.pdf


Report Date : 12 Apr 2010


Pagination or Media Count : 6


Abstract : We calculate the effect of local magnetic moments on the electron-phonon coupling in BaFe2As2+ using the density functional perturbation theory. We show that the magnetism enhances the total electron-phonon coupling by approximately 50%, up to lambda smaller or approximate to 0.35, still not enough to explain the high critical temperature, but strong enough to have a non-negligible effect on superconductivity, for instance, by frustrating the coupling with spin fluctuations and inducing order parameter nodes. The enhancement comes mostly from a renormalization of the electron-phonon matrix elements. We also investigate, in the rigid band approximation, the effect of doping, and find that lambda versus doping does not mirror the behavior of the density of states; while the latter decreases upon electron doping, the former does not, and even increases slightly.


Descriptors :   *COUPLING(INTERACTION) , *ELECTRONS , *PHONONS , *SUPERCONDUCTIVITY , ANTIFERROMAGNETISM , MAGNETIC MOMENTS , DENSITY FUNCTIONAL THEORY , FIRST PRINCIPLES CALCULATIONS


Subject Categories : Electricity and Magnetism
      Nuclear Physics & Elementary Particle Physics


Distribution Statement : APPROVED FOR PUBLIC RELEASE