A Study of Ni-Substitution Effects on Heavy-Fermion CeCu2Si2 - Similarities between Ni Substitution and High-Pressure Effects -

Abstract

The effects of Ni substitution on Ce(Cu1-xNix)2Si2 have been studied by specific heat and electrical resistivity measurements. The specific heat measurement has revealed that the enhanced quantum fluctuations around an antiferromagnetic quantum critical point are markedly suppressed by Ni substitution, and that the Fermi liquid state recovers in the Nirich region (x > 0.12). The characteristic T-linear dependence of the resistivity has been observed at approximately x ~ 0.10 together with a sign of superconductivity. The variation of n in the form of rho - rho0 = aT^n against Tmax^1, at which the resistivity peaks, coincides with the case of high-pressure experiments on pure CeCu2Si2. The anomalous T-linear behavior appears to occur in the crossover region from the Kondo regime to the valence fluctuation regime rather than in the conventional antiferromagnetic quantum critical region.

11 pages, 5 figures, to be published (J. Phys. Soc. Jpn)

References in corpus (3)

• Signatures of valence fluctuations in CeCu2Si2 under high pressure
• Valence Fluctuations Revealed by Magnetic Field Scan: Comparison with Experiments in YbXCu_4 (X=In, Ag, Cd) and CeYIn_5 (Y=Ir, Rh)
• Meta-orbital Transition in Heavy-fermion Systems: Analysis by Dynamical Mean Field Theory and Self-consistent Renormalization Theory of Orbital Fluctuations

Cited by in corpus (1)

• Non-Fermi-liquid behavior at anti-ferromagnetic quantum critical point in heavy fermion system Ce(Cu${}_{1-x}$Co${}_x$)${}_2$Ge${}_2$