Competition and coexistence of magnetic and quadrupolar ordering

TL;DR

This paper explores how magnetic and quadrupolar orders compete and coexist in complex materials, emphasizing the influence of interactions, frustration, and fluctuations on phase diagrams, with a focus on Pr-based skutterudites.

Contribution

It provides a theoretical analysis of the interplay between magnetic and quadrupolar ordering, highlighting the role of local Hilbert space dimensionality and intersite interactions.

Findings

Magnetic fields affect quadrupolar phase transitions.

Complex phase diagrams arise from competing interactions.

Frustration and fluctuations significantly influence ordering phenomena.

Abstract

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 diagrams, 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 some Pr-based skutterudite compounds.