The Ground State of Dilute Tm Systems is Degenerate

Abstract

The ground state of the appropriate generalization of the impurity Anderson model for valence fluctuations between two realistic Tm+2 and Tm+3 configurations is obtained, in the narrowband limit, using the Lanczos' method. This limit describes the strong-coupling fixed point of renormalization group treatments for intermediate valence and Kondo impurities. The resulting ground state is highly degenerate and contains states of total angular momentum 0, 312, 2, 512, 4 and 912. The crystal electric field or an applied magnetic field should split the degeneracy favouring the magnetic states. As found in TmSe, the Tm magnetic moment is anomalously small.

Two-stage three-channel Kondo physics for an FePc molecule on the Au(1 1 1) surface

“…It can also be viewed as the narrow-band limit of the model with all band energies equal to the Fermi energy, and therefore in an appropriate base the localized molecular orbitals, which we denote as d ν only hybridize with a conduction electron orbital c ν of the same symmetry. The resulting finite system can be diagonalized and the result brings useful information on the ground state of the full system [62][63][64]. For example for a Fermi liquid, the ground state of the SCFP and of the full system is a non degenerate singlet, while in the two-channel Kondo model, the ground state of the SCFP is a doublet and the SCFP is unstable, indicating that the full system is a non-Fermi liquid [65,66].…”