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arXiv · 0911.3075

On the nature and anisotropy of $Q \neq 0$ correlations in Tb_2Ti_2O_7 under the application of magnetic fields

J. P. C. Ruff·B. D. Gaulin·K. C. Rule·J. S. Gardner
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Abstract

We report an analysis of neutron diffraction from single crystals of the spin-liquid pyrochlore Tb2Ti2O7 under the application of magnetic fields along the crystallographic $[110]$ direction. Such a perturbation has been shown to destroy the spin liquid ground state and induce long-range order, although the nature of the ordered state was not immediately determined. Recently, it has been proposed that the ordered state is characterized by spin-ice-like correlations, evincing an emergent ferromagnetic tendency in this material despite the large negative Curie-Weiss constant. Here, we argue instead that the ordered state is dominated by $Q \neq 0$ correlations that emerge either from strong antiferromagnetism or magnetoelastic distortion of the crystal. In contrast to previous reports, we observe no evidence for re-entrant behaviour in the high field limit. Extreme sensitivity of the ordered state to the alignment of the applied field is suggested to account for these discrepancies.

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J. P. C. Ruff, B. D. Gaulin, K. C. Rule, J. S. Gardner. 2009-11-16. On the nature and anisotropy of $Q \neq 0$ correlations in Tb_2Ti_2O_7 under the application of magnetic fields. https://arxiv.org/abs/0911.3075

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