Research output: Contribution to journal › Article › peer-review
Unexpected differences between surface and bulk spectroscopic and implied Kondo properties of heavy fermion CeRh2Si2. / Poelchen, Georg; Schulz, Susanne; Mende, Max; Güttler, Monika; Generalov, Alexander; Fedorov, Alexander V.; Caroca-Canales, Nubia; Geibel, Christoph; Kliemt, Kristin; Krellner, Cornelius; Danzenbächer, Steffen; Usachov, Dmitry Yu; Dudin, Pavel; Antonov, Victor N.; Allen, James W.; Laubschat, Clemens; Kummer, Kurt; Kucherenko, Yuri; Vyalikh, Denis V.
In: npj Quantum Materials, Vol. 5, No. 1, 70, 06.10.2020.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Unexpected differences between surface and bulk spectroscopic and implied Kondo properties of heavy fermion CeRh2Si2
AU - Poelchen, Georg
AU - Schulz, Susanne
AU - Mende, Max
AU - Güttler, Monika
AU - Generalov, Alexander
AU - Fedorov, Alexander V.
AU - Caroca-Canales, Nubia
AU - Geibel, Christoph
AU - Kliemt, Kristin
AU - Krellner, Cornelius
AU - Danzenbächer, Steffen
AU - Usachov, Dmitry Yu
AU - Dudin, Pavel
AU - Antonov, Victor N.
AU - Allen, James W.
AU - Laubschat, Clemens
AU - Kummer, Kurt
AU - Kucherenko, Yuri
AU - Vyalikh, Denis V.
N1 - Funding Information: This work was supported by the German Research Foundation (DFG) through Grants No. KR3831/5-1, No. LA655/20-1, Fermi-NEst, GRK1621, and SFB1143 (project-id 247310070). We also acknowledge support from the Spanish Ministry of Economy (MAT-2017-88374-P), the Russian Foundation for Basic Research (Grant No. 20-32-70127), and Saint Petersburg State University (Grant No. ID 51126254). We acknowledge Diamond Light Source for access to beamline I05 (proposals no. SI17761-1 and SI24339-1) where the here presented data were measured. The research leading to this result has been supported by the project CALIPSOplus under Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020. Open Access funding enabled and organized by Projekt DEAL. Publisher Copyright: © 2020, The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/10/6
Y1 - 2020/10/6
N2 - Ultra-violet angle-resolved photoemission spectroscopy (UV-ARPES) was used to explore the temperature dependence of the Ce-4f spectral responses for surface and bulk in the antiferromagnetic Kondo lattice CeRh2Si2. Spectra were taken from Ce- and Si-terminated surfaces in a wide temperature range, and reveal characteristic 4f patterns for weakly (surface) and strongly (bulk) hybridized Ce, respectively. The temperature dependence of the Fermi level peak differs strongly for both cases implying that the effective Kondo temperature at the surface and bulk can be rather distinct. The greatly reduced crystal–electric-field (CEF) splitting at the surface gives reason to believe that the surface may exhibit a larger effective Kondo temperature because of a higher local-moment effective degeneracy. Further, the hybridization processes could strongly affect the 4f peak intensity at the Fermi level. We derived the k-resolved dispersion of the Kondo peak which is also found to be distinct due to different sets of itinerant bands to which the 4f states of surface and bulk Ce are coupled. Overall our study brings into reach the ultimate goal of quantitatively testing many-body theories that link spectroscopy and transport properties, for both the bulk and the surface, separately. It also allows for a direct insight into the broader problem of Kondo lattices with two different local-moment sublattices, providing some understanding of why the cross-talking between the two Kondo effects is weak.
AB - Ultra-violet angle-resolved photoemission spectroscopy (UV-ARPES) was used to explore the temperature dependence of the Ce-4f spectral responses for surface and bulk in the antiferromagnetic Kondo lattice CeRh2Si2. Spectra were taken from Ce- and Si-terminated surfaces in a wide temperature range, and reveal characteristic 4f patterns for weakly (surface) and strongly (bulk) hybridized Ce, respectively. The temperature dependence of the Fermi level peak differs strongly for both cases implying that the effective Kondo temperature at the surface and bulk can be rather distinct. The greatly reduced crystal–electric-field (CEF) splitting at the surface gives reason to believe that the surface may exhibit a larger effective Kondo temperature because of a higher local-moment effective degeneracy. Further, the hybridization processes could strongly affect the 4f peak intensity at the Fermi level. We derived the k-resolved dispersion of the Kondo peak which is also found to be distinct due to different sets of itinerant bands to which the 4f states of surface and bulk Ce are coupled. Overall our study brings into reach the ultimate goal of quantitatively testing many-body theories that link spectroscopy and transport properties, for both the bulk and the surface, separately. It also allows for a direct insight into the broader problem of Kondo lattices with two different local-moment sublattices, providing some understanding of why the cross-talking between the two Kondo effects is weak.
KW - ELECTRONIC-STRUCTURE
KW - CE
KW - CERIUM
KW - METAL
UR - http://www.scopus.com/inward/record.url?scp=85092044209&partnerID=8YFLogxK
U2 - 10.1038/s41535-020-00273-7
DO - 10.1038/s41535-020-00273-7
M3 - Article
AN - SCOPUS:85092044209
VL - 5
JO - npj Quantum Materials
JF - npj Quantum Materials
SN - 2397-4648
IS - 1
M1 - 70
ER -
ID: 70716525