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arXiv · 2009.01670

Nature of Partial Magnetic Order in the Frustrated Antiferromagnet Gd2Ti2O7

Joseph A. M. Paddison·Georg Ehlers·Andrew B. Cairns·Jason S. Gardner·Oleg A. Petrenko·Nicholas P. Butch·Dmitry D. Khalyavin·Pascal Manuel·Henry E. Fischer·Haidong Zhou·Andrew L. Goodwin·J. Ross Stewart
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Abstract

Partially-ordered magnets are distinct from both spin liquids and conventional ordered magnets because order and disorder coexist in the same magnetic phase. Here, we determine the nature of partial order in the canonical frustrated pyrochlore antiferromagnet Gd$_2$Ti$_{2}$O$_{7}$. Using single-crystal neutron-diffraction measurements in applied magnetic field, magnetic symmetry analysis, inelastic neutron-scattering measurements, and spin-wave modeling, we show that its low-temperature magnetic structure involves two propagation vectors (2-$\mathbf{k}$ structure) with suppressed ordered magnetic moments and enhanced spin-wave fluctuations. Our experimental results support theoretical predictions of thermal fluctuation-driven order in Gd$_{2}$Ti$_{2}$O$_{7}$.

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Joseph A. M. Paddison, Georg Ehlers, Andrew B. Cairns, Jason S. Gardner, Oleg A. Petrenko, Nicholas P. Butch, Dmitry D. Khalyavin, Pascal Manuel, Henry E. Fischer, Haidong Zhou, Andrew L. Goodwin, J. Ross Stewart. 2020-09-03. Nature of Partial Magnetic Order in the Frustrated Antiferromagnet Gd2Ti2O7. https://arxiv.org/abs/2009.01670

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