Volume 103, Number 6, September 2013
|Number of page(s)||6|
|Section||Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties|
|Published online||24 September 2013|
Calculated phase diagram of doped BaFe2As2 superconductor in a C4-symmetry breaking model
1 Department of Physics, University of Houston - Houston, TX 77004, USA
2 Theoretical Division, Los Alamos National Laboratory - Los Alamos, NM 87545, USA
3 Center for Integrated Nanotechnologies - Los Alamos, NM 87545, USA
Received: 12 September 2013
Accepted: 13 September 2013
We develop a minimal multiorbital tight-binding model with realistic hopping parameters. The model breaks the symmetry of the tetragonal point group by lowering it from C4 to D2d, which accurately describes the Fermi surface evolution of the electron-doped BaFe2−xCoxAs2 and hole-doped Ba1−yKyFe2As2 compounds. An investigation of the phase diagram with a mean-field Bogoliubov-de Gennes Hamiltonian results in agreement with the experimentally observed electron- and hole-doped phase diagram with only one set of t, U and V parameters. Additionally, the self-consistently calculated superconducting order parameter exhibits -wave pairing symmetry with a small d-wave pairing admixture in the entire doping range, which is the subtle result of the weakly broken symmetry and competing interactions in the multiorbital mean-field Hamiltonian.
PACS: 74.70.Xa – Pnictides and chalcogenides / 74.25.Dw – Superconductivity phase diagrams / 71.10.-w – Theories and models of many-electron systems
© EPLA, 2013
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.