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arXiv · 1501.04927

Crystal field states of Tb3+ in the pyrochlore spin liquid Tb2Ti2O7 from neutron spectroscopy

A. J. Princep·H. C. Walker·D. T. Adroja·D. Prabhakaran·A. T. Boothroyd
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Abstract

We report time-of-flight neutron scattering measurements of the magnetic spectrum of Tb3+ in Tb2Ti2O7. The data, which extend up to 120 meV and have calibrated intensity, enable us to consolidate and extend previous studies of the single-ion crystal field spectrum. We successfully refine a model for the crystal field potential in Tb2Ti2O7 without relying on data from other rare earth titanate pyrochlores, and we confirm that the ground state is a non-Kramers doublet with predominantly |+/-4> components. We compare the model critically with earlier models.

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A. J. Princep, H. C. Walker, D. T. Adroja, D. Prabhakaran, A. T. Boothroyd. 2015-01-20. Crystal field states of Tb3+ in the pyrochlore spin liquid Tb2Ti2O7 from neutron spectroscopy. https://doi.org/10.1103/physrevb.91.224430

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