Interlayer coupling of a two-dimensional kondo lattice with a ferromagnetic surface in the antiferromagnet CeCo2P2

DOI: 10.1021/acsnano.1c10705

Authors: Georg Poelchen (Technische Universität Dresden) , Igor P. Rusinov (St. Petersburg State University) , Susanne Schulz (Technische Universität Dresden) , Monika Guttler (Technische Universität Dresden) , Max Mende (Technische Universität Dresden) , Alexander Generalov (Max IV Laboratory) , Dmitry Yu. Usachov (St. Petersburg State University) , Steffen Danzenbacher (Technische Universität Dresden) , Johannes Hellwig (Goethe-Universität Frankfurt) , Marius Peters (Goethe-Universität Frankfurt) , Kristin Kliemt (Goethe-Universität Frankfurt) , Yuri Kucherenko (G. V. Kurdyumov Institute for Metal Physics, National Academy of Science of Ukraine) , Victor N. Antonov (G. V. Kurdyumov Institute for Metal Physics, National Academy of Science of Ukraine) , Clemens Laubschat (G. V. Kurdyumov Institute for Metal Physics, National Academy of Science of Ukraine) , Evgueni V. Chulkov (G. V. Kurdyumov Institute for Metal Physics, National Academy of Science of Ukraine) , Arthur Ernst (G. V. Kurdyumov Institute for Metal Physics, National Academy of Science of Ukraine) , Kurt Kummer (European Synchrotron Radiation Facility (ESRF)) , Cornelius Krellner (Goethe-Universität Frankfurt) , Denis V. Vyalikh (IKERBASQUE, Basque Foundation for Science)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Acs Nano , VOL 39

State: Published (Approved)
Published: February 2022
Diamond Proposal Number(s): 24339

Abstract: The f-driven temperature scales at the surfaces of strongly correlated materials have increasingly come into the focus of research efforts. Here, we unveil the emergence of a two-dimensional Ce Kondo lattice, which couples ferromagnetically to the ordered Co lattice below the P-terminated surface of the antiferromagnet CeCo2P2. In its bulk, Ce is passive and behaves tetravalently. However, because of symmetry breaking and an effective magnetic field caused by an uncompensated ferromagnetic Co layer, the Ce 4f states become partially occupied and spin-polarized near the surface. The momentum-resolved photoemission measurements indicate a strong admixture of the Ce 4f states to the itinerant bands near the Fermi level including surface states that are split by exchange interaction with Co. The temperature-dependent measurements reveal strong changes of the 4f intensity at the Fermi level in accordance with the Kondo scenario. Our findings show how rich and diverse the f-driven properties can be at the surface of materials without f-physics in the bulk.

Journal Keywords: CeCo2P2; heavy fermion; angle-resolved photoemission spectroscopy; two-dimensional Kondo lattice; antiferromagnetic order; two-dimensional ferromagnetism

Diamond Keywords: Ferromagnetism

Subject Areas: Materials, Physics


Instruments: I05-ARPES

Other Facilities: SIS-ULTRA at SLS

Added On: 16/02/2022 08:19

Discipline Tags:

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

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES)