Tracing the localization of 4f electrons: Angle-resolved photoemission on YbCo2Si2, the stable trivalent counterpart of the heavy-fermion YbRh2Si2

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • M. Guettler - , Chair of Surface Physics (Author)
  • K. Kummer - , European Synchrotron Radiat Facil, European Synchrotron Radiation Facility (ESRF) (Author)
  • S. Patil - , Institute of Solid State and Materials Physics (Author)
  • M. Hoeppner - , TUD Dresden University of Technology, Max Planck Institute for Solid State Research (Author)
  • A. Hannaske - , Max Planck Institute for Chemical Physics of Solids (Author)
  • S. Danzenbaecher - , Chair of Surface Physics (Author)
  • M. Shi - , Paul Scherrer Institute (Author)
  • M. Radovic - , ETH Zurich (Author)
  • E. Rienks - , Helmholtz Centre Berlin for Materials and Energy (Author)
  • C. Laubschat - , Chair of Surface Physics (Author)
  • C. Geibel - , Max Planck Society, Social Neurosci Lab (Author)
  • D. V. Vyalikh - , Chair of Surface Physics, Peter the Great St. Petersburg Polytechnic University (Author)

Abstract

YbCo2Si2 is considered to serve as a stable-valent, isoelectronic reference for the extensively studied heavy-fermion system YbRh2Si2 which is situated very close to an antiferromagnetic quantum critical point (QCP). The investigation of the Fermi surface (FS) topology of YbCo2Si2 and its comparison to YbRh2Si2 could help to unravel the strongly disputed nature of this quantum phase transition, whether it originates from a "local" or "itinerant" QCP. Here we study the electronic structure and FS of YbCo2Si2 by means of angle-resolved photoelectron spectroscopy (ARPES) and compare it to ab initio band structure calculations and FS modeling. Our approach allows the electronic structure at the surface and in the bulk to be disentangled. Identifying the bulk contribution, we demonstrate that YbCo2Si2 exhibits a "small" FS, confirming the formation of a "large" FS in YbRh2Si2. This favors an itinerant QCP, instead of the widely discussed local scenario. Our study demonstrates that ARPES is a reliable tool for the study of bulk electronic states in intermetallic Kondo lattice systems despite the complexity induced by their three-dimensional character and the presence of pronounced surface states.

Details

Original languageEnglish
Article number195138
Number of pages5
JournalPhysical Review B
Volume90
Issue number19
Publication statusPublished - 20 Nov 2014
Peer-reviewedYes

External IDs

Scopus 84915748831

Keywords