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arXiv · 1705.05699

Strong exchange anisotropy in YbMgGaO$_4$ from polarized neutron diffraction

Sándor Tóth·Katharina Rolfs·Andrew R. Wildes·Christian Rüegg
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Abstract

We measured the magnetic correlations in the triangular lattice spin-liquid candidate material YbMgGaO$_4$ via polarized neutron diffraction. The extracted in-plane and out-of-plane components of the magnetic structure factor show clear anisotropy. We found that short-range correlations persist at the lowest measured temperature of 52 mK and neutron scattering intensity is centered at the $M$ middle-point of the hexagonal Brillouin-zone edge. Moreover, we found pronounced spin anisotropy, with different correlation lengths for the in-plane and out-of-plane spin components. When comparing to a self-consistent Gaussian appoximation, our data clearly support a model with only first-neighbor coupling and strongly anisotropic exchanges.

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Sándor Tóth, Katharina Rolfs, Andrew R. Wildes, Christian Rüegg. 2017-05-16. Strong exchange anisotropy in YbMgGaO$_4$ from polarized neutron diffraction. https://arxiv.org/abs/1705.05699

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