Dresden 2017 – wissenschaftliches Programm
TT 53.13: Poster
Mittwoch, 22. März 2017, 15:00–19:00, P2-OG2
Fermi-surface topology of (Rb,Cs)Fe2As2 — •Tobias Förster1, Johannes Klotz1, Kathrin Götze1, Seunghyun Khim2, Helge Rosner2, and Jochen Wosnitza1 — 1Dresden High Magnetic Field Laboratory (HLD-EMFL), Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany — 2Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
The unique Fermi-surface topology of many iron-pnictide superconductors stimulates a number of theories on the nature of the pairing interactions in these materials. In the case of (K,Rb,Cs)Fe2As2, there is an ongoing discussion whether a Lifshitz transition is connected to the superconducting properties of these 122 iron arsenides. Studies of the pressure dependence of HC2 did not find evidence for that kind of transition [1,2]. In contrast, high-resolution band structure calculations show a van-Hove singularity close to the Fermi energy, favouring a Lifshitz transition. In order to investigate the possible impact of this feature, a precise knowledge of the electronic structure is eminent. We, therefore, calculated the Fermi surface of (Rb,Cs)Fe2As2 using the full-potential-local-orbital scheme and started investigating the de Haas-van Alphen effect of (Rb,Cs)Fe2As2 in static fields up to 18 T. In our contribution, we show the first results of our ongoing torque-magnetometry measurements and compare them with the results of our band-structure calculations.
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