Disorder and Quantum spin ice

TL;DR

This study reveals that random strains significantly influence the low-temperature magnetic properties of Pr2Zr2O7, a quantum spin ice candidate, leading to a disordered state with unique short-range correlations and spin-ice-like excitations.

Contribution

It demonstrates how strain disorder affects quantum spin ice behavior and introduces a new disordered state with specific correlations, expanding understanding of quantum spin ice materials.

Findings

Strain distribution explains temperature-dependent specific heat and spin spectra.

Random strains promote a disordered state with short-range antiferroquadrupolar correlations.

Emergence of spin-ice-like excitations in a disordered quantum spin ice.

Abstract

We report on diffuse neutron scattering experiments providing evidence for the presence of random strains in the quantum spin ice candidate Pr2Zr2O7. Since Pr is a non-Kramers ion, the strain deeply modifies the picture of Ising magnetic moments governing the low temperature properties of this material. It is shown that the derived strain distribution accounts for the temperature dependence of the specific heat and of the spin excitation spectra. Taking advantage of mean field and spin dynamics simulations, we argue that the randomness in Pr2Zr2O7, promotes a new state of matter, which is disordered, yet characterized by short range antiferroquadrupolar correlations, and from which emerge spin-ice like excitations. This study thus opens an original research route in the field of quantum spin ice.