Multipole Fluctuations in Filled Skutterudites

In order to clarify exotic multipole properties of filled skutterudites, we evaluate multipole susceptibility for n =1–5, where n is the local f -electron number, on the basis of a multiorbital Anderson model constructed using the j – j coupling scheme. For n =1, magnetic fluctuations dominate over low-temperature electronic properties, while for n =2 and 4, electronic states are dominated by both magnetic and quadrupole fluctuations. For n =3 and 5, octupole fluctuations are found to be significant, depending on the crystalline electric field potential. We discuss the possible relevance of the results to actual materials.