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arXiv · 0811.3367

Dynamical Behavior of Spins in the Rare-Earth Kagomé Pr$_3$Ga$_5$SiO$_{14}$

L. L. Lumata·K. -Y. Choi·T. Besara·M. J. R. Hoch·H. D. Zhou·J. S. Brooks·P. L. Kuhns·A. P. Reyes·N. S. Dalal·C. R. Wiebe
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Abstract

We report on the use of $^{69,71}$Ga nuclear magnetic resonance to probe spin dynamics in the rare-earth kagomé system Pr$_3$Ga$_5$SiO$_{14}$. We find that the spin-lattice relaxation rate $^{69}1/T_1$ exhibits a maximum around 30 K, below which the Pr$^{3+}$ spin correlation time $τ$ shows novel field-dependent behavior consistent with a field-dependent gap in the excitation spectrum. The spin-spin relaxation rate $^{69}1/T_{2}$ exhibits a peak at a lower temperature (10 K) below which field-dependent power-law behavior close to $T^{2}$ is observed. These results point to field-induced formation of nanoscale magnetic clusters consistent with recent neutron scattering measurements.

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L. L. Lumata, K. -Y. Choi, T. Besara, M. J. R. Hoch, H. D. Zhou, J. S. Brooks, P. L. Kuhns, A. P. Reyes, N. S. Dalal, C. R. Wiebe. 2008-11-20. Dynamical Behavior of Spins in the Rare-Earth Kagomé Pr$_3$Ga$_5$SiO$_{14}$. https://arxiv.org/abs/0811.3367

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