Echo of the Quantum Phase Transition of CeCu${}_{6-x}$Au${}_x$ in XPS: Breakdown of Kondo Screening

Abstract

We present an X-ray photoemission study of the heavy-fermion system CeCu${}_{6-x}$Au${}_x$ across the magnetic quantum phase transition of this compound at temperatures above the single-ion Kondo temperature $T_K$. In dependence of the Au concentration $x$ we observe a sudden change of the $f$-occupation number $n_f$ and the core-hole potential $U_{df}$ at the critical concentration $x_c=0.1$. We interpret these findings in the framework of the single-impurity Anderson model. Our results are in excellent agreement with findings from earlier UPS measurements %\cite{klein08qpt} and provide further information about the precursors of quantum criticality at elevated temperatures.

5 pages, 3 figures; published version, references updated, minor changes in wording

References in corpus (3)

• Quantum Criticality in Heavy Fermion Metals
• High Resolution Photoemission Study on Low-T_K Ce Systems: Kondo Resonance, Crystal Field Structures, and their Temperature Dependence
• Signature of quantum criticality in photoemission spectroscopy at elevated temperature

Cited by in corpus (4)

• Multiple quantum phase transitions and superconductivity in Ce-based heavy fermions
• Fermi surface topology of the two-dimensional Kondo lattice model: a dynamical cluster approximation approach
• Nonlocal Kondo effect and quantum critical phase in heavy fermion metals
• Giant spectral renormalization and complex hybridization physics in a Kondo lattice system, CeCuSb2