Transport properties of heavy-fermion systems

Article

关键词: RENORMALIZATION-GROUP APPROACH;    PERIODIC ANDERSON MODEL;    U-PERTURBATION APPROACH;    DILUTE MAGNETIC-ALLOYS;    HUBBARD-MODEL;    STATIC PROPERTIES;    LIQUID BEHAVIOR;    LATTICE MODEL;    ENERGY SCALE;    SELF-ENERGY;   

DOI  :  10.1103/PhysRevB.74.195119

来源: SCIE

【 摘 要 】

We calculate the temperature dependence of the transport properties of heavy-fermion systems such as resistivity, optical conductivity, thermoelectric power, the electronic part of the thermal conductivity, and the figure of merit. The one-particle properties of the periodic Anderson model are obtained within dynamical mean-field theory for the paramagnetic phase using Wilson's numerical renormalization group and the modified perturbation theory as impurity solvers. We discuss the dependence of the transport properties on the band filling, valence, and Coulomb correlation U. The typical experimental findings can be reproduced and understood, in particular the temperature dependence of the resistance and the thermoelectric power and their absolute magnitude for both metallic heavy-fermion systems and Kondo insulators. For large values of U, we find a negative Seebeck coefficient S(T) for an intermediate-temperature regime as observed in S(T) of CeCu2Si2. We analyze different estimates for possible characteristic low-temperature scales of the lattice. Our results indicate a one-parameter scaling of thermodynamic and some transport properties with a strongly occupancy-dependent scaling function. This is consistent with a strong-coupling local Fermi-liquid fixed point of the effective site governing all low-lying excitations for T -> 0 in the paramagnetic phase.

【 授权许可】

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