1 research outputs found
Construction of a Microscopic Model for Yb and Tm Compounds on the Basis of a \mib{j}-\mib{j} Coupling Scheme
We provide a prescription to construct a microscopic model for heavy
lanthanide systems such as Yb and Tm compounds by exploiting a - coupling
scheme. Here we consider a situation with a large spin-orbit coupling, in which
=5/2 sextet is fully occupied, while =7/2 octet is partially occupied,
where denotes total angular momentum. We evaluate crystalline electric
field potentials and Coulomb interactions among the states of the =7/2 octet
to construct a local Hamiltonian in the - coupling scheme. Then, it is
found that the local -electron states composed of the =7/2 octet agree
quite well with those of seven orbitals even for a realistic value of the
spin-orbit coupling. As an example of the application of the present model, we
discuss low-temperature multipole states of Yb- and Tm-based filled
skutterudites by analyzing multipole susceptibility of the Anderson model in
the - coupling scheme with the use of a numerical renormalization group
technique. From the comparison with the numerical results of the seven-orbital
Anderson model, it is concluded that the multipole state is also well
reproduced by the - coupling model, even when we include the
hybridization between conduction and electrons for the realistic value of
the spin-orbit coupling. Finally, we briefly discuss future applications of the
present prescription for theoretical research on heavy lanthanide compounds.Comment: 12 pages, 8 figures