COMPETITION AND COEXISTENCE OF MAGNETIC AND QUADRUPOLAR ORDERING

摘要

The large number of low-lying states of d- and f-shells supports a variety of order parameters. The effective dimensionality of the local Hilbert space depends on the strength, and kind, of intersite interactions. This gives rise to complicated phase dia,-grarns, and an enhanced role of frustration and fluctuation effects. The general principles are illustrated on the example of the effect of a magnetic field on quadrupolar phase transitions in the Pr-filled skutterudite PrFe_4P_(12).