Parts | Days | Selection | Search | Updates | Downloads | Help
TT: Fachverband Tiefe Temperaturen
TT 10: Topology: Majorana Physics I
TT 10.8: Talk
Monday, March 18, 2024, 17:00–17:15, H 2053
Quest for topological bands in magnetic chains on superconductors — •András Lászlóffy1, Bendegúz Nyári2, Nóra Kucska1, László Szunyogh2, and Balázs Újfalussy1 — 1HUN-REN Wigner Research Centre for Physics, Budapest, Hungary — 2Budapest University of Technology and Economics, Budapest, Hungary
In magnetic chains placed on superconductors, Shiba bands are formed within the superconducting gap. Spin-orbit coupling or a spin-spiral configuration can lead to the hybridization of Shiba bands which can open a topologically non-trivial gap around the Fermi energy. Simple models are suitable to understand which effects assist the formation of topological band structure, but provide no recipe how this works out in real situations. To have a quantitative and realistic description of these systems, we solve the Kohn-Sham-Dirac Bogoliubov-de Gennes equations within the Korringa-Kohn-Rostoker multiple scattering theory. We demonstrate that by scaling the magnetic moment in the spin spirals, several, however, narrow regions can be found where the system is topological. By adding a non-magnetic overlayer between the superconductor and the chain, we explore the topological properties of a large variety of systems in terms of changing the crystallographic direction of the chain and the magnetic configuration.
Keywords: superconductor; band inversion; magnetic chain; magnetic spiral state; spin-orbit coupling