Dresden 2014 – wissenschaftliches Programm
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TT: Fachverband Tiefe Temperaturen
TT 68: Superconductivity: Fe-based Superconductors - Theory I
TT 68.3: Vortrag
Mittwoch, 2. April 2014, 15:45–16:00, HSZ 201
Electronic and Magnetic Properties of Ba(Fe1−xCox)2As2 — •Gerald Derondeau, Sergiy Mankovsky, Hubert Ebert, and Ján Minár — Department Chemie, Ludwig-Maximilians-Universität München, 81377 München, Germany
Characteristic for most iron arsenides is an antiferromagnetic ordering in form of a commensurate spin-density wave (SDW) at low temperatures, often coupled with a structural phase transition. Superconductivity emerges when these transitions are suppressed, e.g. by chemical doping. As many DFT calculations have still problems to accurately describe the magnetic state [1] further investigations on this issue are needed.
We investigated the low-temperature orthorhombic phase of Ba(Fe1−xCox)2As2 using the Korringa-Kohn-Rostoker-Green function (KKR-GF) [2] approach which allows inclusion of chemical disorder via the coherent potential approximation (CPA).
To examine the magnetic structure with different spin states we used a full magnetic unit cell with 8 Fe atoms and antiferromagnetic ordering. In addition spin-spiral calculations for the q-dependent induced magnetization were performed to account for the SDW state.
Furthermore, the doping dependent evolution of the strong in-plane anisotropy of the electronic structure as observed in ARPES measurements [3] was investigated and connected to the magnetic behavior.
I. I. Mazin, M. D. Johannes, Nature Phys. 5, 141 (2009)
H. Ebert, D. Ködderitzsch, J. Minár, Rep. Prog. Phys. 74, 96501 (2011)
M. Yi, D. Lu, J.-H. Chu, et al., PNAS 108, 6878 (2011)