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arXiv · 1912.04913

Multiphase Magnetism in Yb2Ti2O7

A. Scheie·J. Kindervater·S. Zhang·H. J. Changlani·G. Sala·G. Ehlers·A. Heinemann·G. S. Tucker·S. M. Koohpayeh·C. Broholm
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Abstract

We document the coexistence of ferro- and anti-ferromagnetism in pyrochlore $\rm Yb_2Ti_2O_7$ using three neutron scattering techniques on stoichiometric crystals: elastic neutron scattering shows a canted ferromagnetic ground state, neutron scattering shows spin wave excitations from both a ferro-and an antiferro-magnetic state, and field and temperature dependent small angle neutron scattering reveals the corresponding anisotropic magnetic domain structure. High-field $\langle 111 \rangle$ spin wave fits show that $\rm Yb_2Ti_2O_7$ is extremely close to an antiferromagnetic phase boundary. Classical Monte Carlo simulations based on the interactions inferrred from high field spin wave measurements confirm $\psi_2$ antiferromagnetism is metastable within the FM ground state.

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A. Scheie, J. Kindervater, S. Zhang, H. J. Changlani, G. Sala, G. Ehlers, A. Heinemann, G. S. Tucker, S. M. Koohpayeh, C. Broholm. 2019-12-10. Multiphase Magnetism in Yb2Ti2O7. https://doi.org/10.1073/pnas.2008791117

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