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arXiv · 1504.03003

{23}Na nuclear spin-lattice relaxation studies of Na2Ni2TeO6

Y. Itoh
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Abstract

We report on {23}Na NMR studies of a honeycomb lattice antiferromagnet Na2Ni2TeO6 by {23}Na nuclear spin-echo techniques. The {23}Na nuclear spin-lattice relaxation rate 1/{23}T_1 exhibits critical divergence near a Neel temperature T_N = 26 K, a narrow critical region, and a critical exponent w = 0.34 in 1/{23}T_1 = a (T/T_N - 1)^{-w} for Na2Ni2TeO6, and T_N = 18 K for Na2(Ni{0.5}Cu{0.5})2TeO6. Although the uniform magnetic susceptibility of Na2Ni2TeO6 exhibits a broad maximum at 35 K characteristic of low dimensional spin systems, the NMR results indicate three dimensional critical phenomenon around the Neel temperature.

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Y. Itoh. 2015-04-12. {23}Na nuclear spin-lattice relaxation studies of Na2Ni2TeO6. https://doi.org/10.7566/jpsj.84.064714

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