Spin orientation of two-dimensional electrons driven by temperature-tunable competition of spin–orbit and exchange–magnetic interactions

DOI: 10.1021/acs.nanolett.6b04036

Authors: Alexander Generalov (MAX IV Laboratory, Lund University) , Mikhail M. Otrokov (Donostia International Physics Center (DIPC); Tomsk State University) , Alla Chikina (Dresden University of Technology) , Kristin Kliemt (Goethe-Universität Frankfurt) , Kurt Kummer (European Synchrotron Radiation Facility) , Marc Höppner (Max Planck Institute for Solid State Research) , Monika Guttler (Dresden University of Technology) , Silvia Seiro (Max Planck Institute for Chemical Physics of Solids) , Alexander Fedorov (IFW Dresden) , Susanne Schulz (Dresden University of Technology) , Steffen Danzenbächer (Dresden University of Technology) , Evgueni V. Chulkov (Donostia International Physics Center (DIPC); Tomsk State University; Saint Petersburg State University) , Christoph Geibel (Max Planck Institute for Chemical Physics of Solids) , Clemens Laubschat (Dresden University of Technology) , Pavel Dudin (Diamond Light Source) , Moritz Hoesch (Diamond Light Source) , Timur Kim (Diamond Light Source) , Milan Radovic (Swiss Light Source; Paul Scherrer Institute) , Ming Shi (Swiss Light Source) , Nicholas C. Plumb (Swiss Light Source) , Cornelius Krellner (Goethe-Universität Frankfurt) , Denis V. Vyalikh (Donostia International Physics Center (DIPC); Dresden University of Technology; Basque Foundation for Science; Saint Petersburg State University)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nano Letters

State: Published (Approved)
Published: January 2017
Diamond Proposal Number(s): 11512

Abstract: Finding ways to create and control the spin-dependent properties of two-dimensional electron states (2DESs) is a major challenge for the elaboration of novel spin-based devices. Spin–orbit and exchange–magnetic interactions (SOI and EMI) are two fundamental mechanisms that enable access to the tunability of spin-dependent properties of carriers. The silicon surface of HoRh2Si2 appears to be a unique model system, where concurrent SOI and EMI can be visualized and controlled by varying the temperature. The beauty and simplicity of this system lie in the 4f moments, which act as a multiple tuning instrument on the 2DESs, as the 4f projections parallel and perpendicular to the surface order at essentially different temperatures. Here we show that the SOI locks the spins of the 2DESs exclusively in the surface plane when the 4f moments are disordered: the Rashba-Bychkov effect. When the temperature is gradually lowered and the system experiences magnetic order, the rising EMI progressively competes with the SOI leading to a fundamental change in the spin-dependent properties of the 2DESs. The spins rotate and reorient toward the out-of-plane Ho 4f moments. Our findings show that the direction of the spins and the spin-splitting of the two-dimensional electrons at the surface can be manipulated in a controlled way by using only one parameter: the temperature.

Journal Keywords: antiferromagnetism; ARPES; exchange−magnetic interaction; rare-earth intermetallics; Spin−orbit coupling

Diamond Keywords: Antiferromagnetism; Spintronics

Subject Areas: Materials, Physics


Instruments: I05-ARPES

Other Facilities: X09LA at Swiss Light Source; 1-cubed ARPES at BESSY-II

Added On: 05/01/2017 13:37

Discipline Tags:

Quantum Materials Physics Electronics Magnetism Materials Science

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES)