Related papers: Interpretation of experimental results on Kondo sy…
We calculate the Kondo temperature ($T_K$) and crystal-field levels of strongly correlated multiorbital systems solving the Anderson Impurity Model with the finite U Non-Crossing Approximation (UNCA) in its simplest scheme, that is,…
Possible Kondo effect in Pr skutterudite is studied with attention to characteristic features of low-lying crystalline electric field (CEF) levels and the conduction band. A mechanism for the small CEF splitting between a singlet and a…
The thermodynamic Bethe ansatz equations for the N = 6 Coqblin-Schrieffer model with crystal fields have been solved numerically. The realistic case of three Kramers doublets with arbitrary splittings has been studied for the first time.…
Dynamics of the singlet-triplet crystalline electric field (CEF) system at finite temperatures is discussed by use of the non-crossing approximation. Even though the Kondo temperature is smaller than excitation energy to the CEF triplet,…
The thermodynamic Bethe ansatz equations for the Coqblin-Schrieffer model have been solved for the first time to obtain the magnetic susceptibility in the presence of crystal fields for non-zero temperatures. For the case of N = 4 effective…
We have calculated the band-$f$ hybridizations for Ce$_x$La$_{1-x}$M$_3$ compounds ($x=1$ and $x\rightarrow 0$; M=Pb, In, Sn, Pd) within the local density approximation and fed this into a non-crossing approximation for the Anderson…
We present a high-resolution photoemission study on the strongly correlated Ce-compounds CeCu_6, CeCu_2Si_2, CeRu_2Si_2, CeNi_2Ge_2, and CeSi_2. Using a normalization procedure based on a division by the Fermi-Dirac distribution we get…
Dynamical properties are studied numerically for a variant of the Kondo model with singlet and triplet crystalline electric field (CEF) levels where Kondo and CEF singlets compete for the ground state. Using the continuous-time quantum…
We present high-resolution photoemission spectroscopy studies on the Kondo resonance of the strongly-correlated Ce system CeCu$_2$Si$_2$. Exploiting the thermal broadening of the Fermi edge we analyze position, spectral weight, and…
We study strongly correlated states in triangular artificial atoms. Symmetry-driven orbital degeneracy of the single particle states can give rise to an SU(4) Kondo state with entangled orbital and spin degrees of freedom, and a…
We have succeeded in synthesizing of single crystals of a new intermetallic compound, Ce$_{3}$Rh$_{4}$Pb$_{13}$. Magnetic susceptibility measurements indicate that the Ce moments are highly localized, despite the metallic character of the…
We report measurements of inelastic neutron scattering, magnetic susceptibility, magnetization, and the magnetic field dependence of the specific heat for the heavy Fermion compounds Ce$_3$In and Ce$_3$Sn. The neutron scattering results…
We investigate the electronic structure of cobalt atoms on a copper surface and in a copper host by combining density functional calculations with a numerically exact continuous-time quantum Monte Carlo treatment of the five-orbital…
The recently reported unusual behavior of the static and dynamical magnetic susceptibility as well as the specific heat in Ce$_{1-x}$La$_{x}$Ni$_{9}$Ge$_4$ has raised the question of a possible non-Fermi liquid ground state in this…
We study a realistic Kondo model for crystal field quartet ground states having magnetic and non-magnetic (quadrupolar) exchange couplings with conduction electrons, using the numerical renormalization group method. We focus on a local…
We study the evolution of the Kondo effect in heavy fermion compounds, Yb(Fe$_{1-x}$Co$_{x}$)$_{2}$Zn$_{20}$ (0$\leqslant$ x $\leqslant$ 1), by means of temperature-dependent electric resistivity and specific heat. The ground state of…
Substitution of nickel by copper in the heavy fermion system CeNi$_{9-x}$Cu$_x$Ge$_4$ alters the local crystal field environment of the Ce$^{3+}$-ions. This leads to a quantum phase transition near $x\approx0.4$, which is not only driven by…
This article describes some recently obtained results on the low-energy properties of the "Kondo quartet" model of two spin-1/2 impurities interacting with two channels (flavours) of conduction electrons. We shall particularly emphasize the…
An empirical formula is proposed to calculate the Kondo temperature in quantum point contacts from the Zeeman splitting. A similar formula was used in the point-contact spectroscopy (PCS) method to obtain from the Zeeman splitting of the…
The filled skutterudite compound SmOs_{4}Sb_{12} was prepared in single crystal form and characterized. The SmOs_{4}Sb_{12} crystals have the LaFe_{4}P_{12}-type structure with lattice parameter a = 9.3085 Angstroms. Specific heat…