Dresden 2017 – wissenschaftliches Programm
TT 53.20: Poster
Mittwoch, 22. März 2017, 15:00–19:00, P2-OG2
Tetragonal magnetic order and superconductivity in iron pnictides — •Chris Koschenz and Carsten Timm — Institute of Theoretical Physics, Technische Universität Dresden
Multiband and multiorbital physics is crucial for understanding superconductivity and magnetism in iron pnictides. We employ a realistic multiorbital model to study the newly discovered tetragonal magnetic phase in Bax − 1 Nax Fe2 As2 and Ba1−xKxFe2As2.This additional fourfold symmetric phase is observed in Bax − 1 Nax Fe2 As2 by neutron powder diffraction close to the suppression of the spin-density-wave (SDW) order and is in agreement with the scenario of magnetically driven nematic order.
We elucidate the role played by orbital effects and compare them to other multiorbital systems. Furthermore, we study the coexistence and competition of tetragonal magnetic order and superconductivity as well as the possibility of additional phase transitions in this regime.