Theory of magnetostriction for multipolar quantum spin ice in pyrochlore materials

TL;DR

This paper develops a theoretical framework to detect multipolar quantum spin ice and related phases in pyrochlore materials using magnetostriction, aiding the identification of exotic quantum states.

Contribution

It introduces a theoretical approach to identify multipolar quantum spin ice phases via magnetostriction measurements in pyrochlore materials.

Findings

Theoretical predictions for magnetostriction signatures of multipolar phases.

Contrast between behaviors of non-Kramers and Kramers ions.

Guidance for experimental detection of quantum spin liquids.

Abstract

Multipolar magnetism is an emerging field of quantum materials research. The building blocks of multipolar phenomena are magnetic ions with a non-Kramers doublet, where the orbital and spin degrees of freedom are inextricably intertwined, leading to unusual spin-orbital entangled states. The detection of such subtle forms of matter has, however, been difficult due to a limited number of appropriate experimental tools. In this work, motivated by a recent magnetostriction experiment on Pr$_2$Zr$_2$O$_7$, we theoretically investigate how multipolar quantum spin ice, an elusive three dimensional quantum spin liquid, and other multipolar ordered phases in the pyrochlore materials can be detected using magnetostriction. We provide theoretical results based on classical and/or quantum studies of non-Kramers and Kramers magnetic ions, and contrast the behaviors of distinct phases in both systems. Our work paves an important avenue for future identification of exotic ground states in multipolar systems.