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The pyrochlore antiferromagnet Ce₂Zr₂O₇ is sensitive to an instability of the Ce³⁺ oxidation state, whereby the 4f¹ electronic configuration of Ce³⁺ can be diluted via sample oxidation and the concomitant introduction of Ce⁴⁺ to the lattice.¹ For that reason, reduction of Ce₂Zr₂O₇ samples is required to enable a neutron scattering study of this material, the subject of this presentation. The spins in Ce₂Zr₂O₇ possess a local Ising anisotropy and interact via an antiferromagnetic coupling, which typically results in all-in all-out antiferromagnetic order. However the crystal electric field (CEF) wavefunctions of the Ce³⁺ ground state can have a dipole-octupole nature which is an ingredient for moment fragmentation and can allow for a disordered U(1) quantum spin liquid ground state.² High energy neutron spectroscopy confirms the dipole-octupole CEF ground state, and higher energy resolution inelastic neutron scattering shows a disordered ground state for Ce₂Zr₂O₇.

1. S. Urban et al., Chem. Mater. 29 (21) (2017) 9218-9226
2. Y.D. Li et al., Phys. Rev. B 95 (4) 041106(R) (2017)