Coulombic antiferromagnet in spin-1/2 pyrochlores with dipole-octupole doublets

TL;DR

This paper investigates a novel Coulombic antiferromagnetic state in spin-1/2 pyrochlores with dipole-octupole doublets, revealing emergent quantum electrodynamics and fractionalized excitations coexisting with magnetic order.

Contribution

It introduces a fractionalized antiferromagnetic phase with emergent gauge fields and quasiparticles in pyrochlore magnets, expanding understanding of exotic states in ordered systems.

Findings

Large T^3 specific heat observed

Broad spinon continuum detected in neutron scattering

Emergent quantum electrodynamics characterized in the material

Abstract

Exotic state of matter could coexist with conventional orders such that the gauge fields and fractionalized excitations could prevail in a seemingly ordered state. We explore the Coulombic antiferromagnet in the spin-1/2 pyrochlores with dipole-octupole doublets. This fractionalized antiferromagnetic state carries both antiferromagnetic order and emergent quantum electrodynamics with the gapless gauge photon and fractionalized quasiparticles. We explain the characteristic physical properties including the thermodynamics and the dynamics of this exotic state. This includes for example the anomalously large $T^3$ specific heat and the broad spinon continuum in the inelastic neutron scattering. We discuss the experimental and material's relevance and expect this work to inspire interests in the search of exotic physics among the ordered magnets.