Dipolar-octupolar correlations and hierarchy of exchange interactions in Ce₂Hf₂O₇

2023/05/14 by Porée, Victor, Bhardwaj, Anish, Lhotel, Elsa +9 · 2 citations
#FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Strongly Correlated Electrons (cond-mat.str-el)

paper · doi:10.48550/arxiv.2305.08261

Abstract

High-resolution neutron spectroscopy on Ce₂Hf₂O₇ reveals a correlated state characterized by distinct dipolar scattering signals -- quasi-elastic and inelastic contributions consistent with `photon' and `spinon' excitations in quantum spin ice. These signals coexist with weak octupolar scattering. Fits of thermodynamic data using numerical methods indicate a dominant octupolar exchange, J_x or J_y, with substantial dipolar J_z and minute dipole-octupole J_xz couplings. The J_xz value is corroborated by an independent fit of the neutron scattering amplitude balance between dipolar and octupolar `photon' contributions, highlighting its importance to understand neutron scattering results in this family. Ce<sub>2</sub>Hf<sub>2</sub>O<sub>7</sub> enriches the landscape of dipole-octupole pyrochlore physics, and reveals a `quantum multipolar liquid' where hybrid correlations involve multiple terms in moment series expansion, opening questions on their intertwining and hierarchy in quantum phases.

Cited by

• Fragmented Spin Liquid and Shadow Pinch Points in Dipole-Octupole Pyrochlore Spin Systems
• Disorder-induced proximate quantum spin ice phase in Pr₂Sn₂O₇

Related

• The case for a U(1)_π Quantum Spin Liquid Ground State in the Dipole-Octupole Pyrochlore Ce₂Zr₂O₇
• Two-Peak Heat Capacity Accounts for Rln(2) Entropy and Ground State Access in the Dipole-Octupole Pyrochlore Ce₂Hf₂O₇
• Emergent photons and fractionalized excitations in a quantum spin liquid
• Quantum Spin Liquids in Pyrochlore Magnets With Non-Kramers Local Moments
• Signatures of field-induced multi-color kagome spin liquids in the dipole-octupole pyrochlore Ce₂Hf₂O₇