Abstract
Yb2Si2Al may be a prototype for exploring different aspects of the Shastry-Sutherland lattice, formed by planes of orthogonally coupled Yb ions. Measurements of the magnetic susceptibility find incoherently fluctuating Yb3+ moments coexisting with a weakly correlated metallic state that is confirmed by measurements of the electrical resistivity. Increasing signs of Kondo coherence are found with decreasing temperature, including an enhanced Sommerfeld coefficient and Kadowaki-Woods ratio that signal that the metallic state found at the lowest temperatures is a Fermi liquid where correlations have become significantly stronger. A pronounced peak in the electronic and magnetic specific heat indicates that the coupling of the Yb moments to the conduction electrons leads to an effective Kondo temperature that is approximately 30 K. The valence of Yb2Si2Al has been investigated with electron spectroscopy methods. Yb2Si2Al is found to be strongly intermediate valent [vF=2.68(2) at 80 K]. Taken together, these experimental data are consistent with a scenario where a coherent Kondo lattice forms in Yb2Si2Al from an incoherently fluctuating ensemble of Yb moments with incomplete Kondo compensation, and strong intermediate valence character.
Original language | English |
---|---|
Article number | 075101 |
Journal | Physical Review B |
Volume | 98 |
Issue number | 7 |
DOIs | |
State | Published - Aug 1 2018 |
Bibliographical note
Publisher Copyright:© 2018 American Physical Society.
Funding
Work at Texas A&M University (W.J.G. and M.C.A) was supported by the National Science Foundation under Grant No. NSF-DMR-1310008 and K.C., M.S., and A.S. benefited from the financial support of the Deutsche Forschungsgemeinschaft (DFG) under Grant No. SE-1441/1-2.
Funders | Funder number |
---|---|
National Science Foundation (NSF) | 1807451, NSF-DMR-1310008 |
Texas AandM University | |
Deutsche Forschungsgemeinschaft |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics