Spin structure of spin-orbit split surface states in a magnetic material revealed by spin-integrated photoemission

DOI: 10.1103/PhysRevB.101.245140

Authors: D. Y. Usachov (St. Petersburg State University) , M. Guttler (Technische Universität Dresden) , S. Schulz (Institut für Festkörper- und Materialphysik,) , G. Poelchen (Technische Universität Dresden) , S. Seiro (Leibniz IFW Dresden) , K. Kliemt (Goethe-Universität Frankfurt) , K. Kummer (European Synchrotron Radiation Facility (ESRF)) , C. Krellner (Goethe-Universität Frankfurt) , C. Laubschat (Technische Universität Dresden) , E. V. Chulkov (St. Petersburg State University; Donostia International Physics Center (DIPC); UPV/EHU; CFM-MPC; CSIC-UPV/EHU; Tomsk State University) , D. V. Vyalikh (Donostia International Physics Center (DIPC); IKERBASQUE, Basque Foundation for Science)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Physical Review B , VOL 101

State: Published (Approved)
Published: June 2020
Diamond Proposal Number(s): 18844 , 17761

Abstract: The emergence of ferromagnetism in Rashba systems, where the evolving exchange interaction enters into competition with spin-orbit coupling, leads to a nontrivial spin-polarized electronic landscape with an intricate momentum-dependent spin structure, which is challenging to unveil. Here, we show a way to disentangle the contributions from the effective spin-orbit and exchange fields and thus to gain knowledge of the spin structure in ferromagnetic Rashba materials, which is required for spintronic applications. Our approach is based exclusively on spin-integrated photoemission measurements combined with a two-band modeling. As an example, we consider the mixed-valent material EuIr 2 Si 2 which, while being nonmagnetic in the bulk, reveals strong ferromagnetism at the iridium-silicide surface where both spin-orbit and exchange magnetic interactions coexist. The combined effect of these interactions causes a complex band dispersion of the surface state which can be observed in photoemission experiments. Our method allows us to comprehensively unravel the surface-state spin structure driven by spin-orbit coupling at the ferromagnetic surface. This approach opens up opportunities to characterize the spin structure of ferromagnetic Rashba materials, especially where dedicated spin-resolved measurements remain challenging.

Journal Keywords: Electronic structure; Exchange interaction; Ferromagnetism; Spin polarization; Spin-orbit coupling; Surface states

Diamond Keywords: Spintronics; Ferromagnetism

Subject Areas: Materials, Physics


Instruments: I05-ARPES

Added On: 25/06/2020 09:18

Documents:
PhysRevB.101.245140.pdf

Discipline Tags:

Quantum Materials Physics Hard condensed matter - structures Electronics Magnetism Materials Science

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES)