Emerging 2D-ferromagnetism and strong spin-orbit coupling at the surface of valence-fluctuating EuIr2Si2

DOI: 10.1038/s41535-019-0166-z

Authors: Susanne Schulz (Technische Universität Dresden) , Ilya A. Nechaev (Centro de Física de Materiales CFM-MPC; Centro Mixto CSIC-UPV/EHU; Donostia International Physics Center (DIPC)) , Monika Güttler (Technische Universität Dresden) , Georg Poelchen (Technische Universität Dresden) , Alexander Generalov (MAX IV Laboratory, Lund University) , Steffen Danzenbächer (Technische Universität Dresden) , Alla Chikina (Swiss Light Source) , Silvia Seiro (IFW Dresden) , Kristin Kliemt (Goethe-Universität Frankfurt) , Alexandra Yu. Vyazovskaya (Tomsk State University; Saint Petersburg State University) , Timur K. Kim (Diamond Light Source) , Pavel Dudin (Diamond Light Source) , Evgueni V. Chulkov (Centro de Física de Materiales CFM-MPC; Centro Mixto CSIC-UPV/EHU; Donostia International Physics Center (DIPC); Tomsk State University; Saint Petersburg State University) , Clemens Laubschat (Technische Universität Dresden) , Eugene E. Krasovskii (Donostia International Physics Center (DIPC); Departamento de Física de Materiales UPV/EHU; IKERBASQUE, Basque Foundation for Science) , Christoph Geibel (Max-Planck-Institut für Chemische Physik fester Stoffe) , Cornelius Krellner (Goethe-Universität Frankfurt) , Kurt Kummer (European Synchrotron Radiation Facility (ESRF)) , Denis V. Vyalikh (Donostia International Physics Center (DIPC); IKERBASQUE, Basque Foundation for Science)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Npj Quantum Materials , VOL 4

State: Published (Approved)
Published: June 2019
Diamond Proposal Number(s): 18844 , 17761

Abstract: The development of materials that are non-magnetic in the bulk but exhibit two-dimensional (2D) magnetism at the surface is at the core of spintronics applications. Here, we present the valence-fluctuating material EuIr2Si2, where in contrast to its non-magnetic bulk, the Si-terminated surface reveals controllable 2D ferromagnetism. Close to the surface the Eu ions prefer a magnetic divalent configuration and their large 4f moments order below 48 K. The emerging exchange interaction modifies the spin polarization of the 2D surface electrons originally induced by the strong Rashba effect. The temperature-dependent mixed valence of the bulk allows to tune the energy and momentum size of the projected band gaps to which the 2D electrons are confined. This gives an additional degree of freedom to handle spin-polarized electrons at the surface. Our findings disclose valence-fluctuating rare-earth based materials as a very promising basis for the development of systems with controllable 2D magnetic properties which is of interest both for fundamental science and applications.

Journal Keywords: Electronic properties and materials; Magnetic properties and materials

Diamond Keywords: Ferromagnetism

Subject Areas: Physics, Materials


Instruments: I05-ARPES

Added On: 10/06/2019 14:54

Documents:
s41535-019-0166-z.pdf

Discipline Tags:

Surfaces Quantum Materials Hard condensed matter - electronic properties Physics Magnetism Materials Science

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES)