Robust and tunable itinerant ferromagnetism at the silicon surface of the antiferromagnet GdRh2Si2

DOI: 10.1038/srep24254

Authors: M. Güttler (Dresden University of Technology) , A. Generalov (Maxlab Lund University) , M. M. Otrokov (Donostia International Physics Center (DIPC)) , K. Kummer (European Synchrotron Radiation Facility (ESRF)) , K. Kliemt (Goethe-Universität Frankfurt) , A. Fedorov (IFW Dresden) , A. Chikina (TU Dresden) , S. Danzenbächer (TU Dresden) , S. Schulz (Dresden University of Technology) , E. V. Chulkov (Donostia International Physics Center (DIPC)) , Y. M. Koroteev (Tomsk State University) , N. Caroca-Canales (Max Planck Institute for Chemical Physics of Solids) , M. Shi (Swiss Light Source) , M. Radovic (Swiss Light Source) , C. Geibel (Max Planck Institute for Chemical Physics of Solids) , C. Laubschat (Dresden University of Technology) , P. Dudin (Diamond Light Source) , T. Kim (Diamond Light Source) , M. Hoesch (Diamond Light Source) , C. Krellner (Goethe-Universität Frankfurt) , D. Vyalikh (TU Dresden)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Scientific Reports , VOL 6

State: Published (Approved)
Published: April 2016
Diamond Proposal Number(s): 11512

Abstract: Spin-polarized two-dimensional electron states (2DESs) at surfaces and interfaces of magnetically active materials attract immense interest because of the idea of exploiting fermion spins rather than charge in next generation electronics. Applying angle-resolved photoelectron spectroscopy, we show that the silicon surface of GdRh2Si2 bears two distinct 2DESs, one being a Shockley surface state, and the other a Dirac surface resonance. Both are subject to strong exchange interaction with the ordered 4f-moments lying underneath the Si-Rh-Si trilayer. The spin degeneracy of the Shockley state breaks down below ~90 K, and the splitting of the resulting subbands saturates upon cooling at values as high as ~185 meV. The spin splitting of the Dirac state becomes clearly visible around ~60 K, reaching a maximum of ~70 meV. An abrupt increase of surface magnetization at around the same temperature suggests that the Dirac state contributes significantly to the magnetic properties at the Si surface. We also show the possibility to tune the properties of 2DESs by depositing alkali metal atoms. The unique temperature-dependent ferromagnetic properties of the Si-terminated surface in GdRh2Si2 could be exploited when combined with functional adlayers deposited on top for which novel phenomena related to magnetism can be anticipated.

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

Diamond Keywords: Ferromagnetism

Subject Areas: Physics, Materials


Instruments: I05-ARPES

Other Facilities: ID32 at ESRF; SIS X09LA at SLS; One-cubed ARPES at BESSY-II

Added On: 18/04/2016 12:00

Documents:
srep24254.pdf

Discipline Tags:

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

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES)