Critical Slowing Down of Triangular Lattice Spin-3/2 Heisenberg Antiferromagnet Li7RuO6 via 7Li NMR

Abstract

We report 7Li NMR studies of single crystals of triangular-lattice Heisenberg antiferromagnet Li7RuO6. Slow critical divergence with a wide critical region of |T/TN - 1|< 7 was observed in 7Li nuclear spin-lattice relaxation rate. The slowing down of staggered spin fluctuations was analyzed in a renormalized classical region of a two-dimensional triangular-lattice non-linear sigma model. A spin stiffness constant was found to reduce to about 20 % from the value in a spin-wave approximation. The effect of spin frustration, e.g., Z2 vortex excitations on the critical phenomena is suggested.

4 pages, 5 figures, the references were updated, to be published in J. Phys. Soc. Jpn. 78 (2009) No.2

References in corpus (5)

• Universal Magnetic Properties of Frustrated Quantum Antiferromagnets in Two Dimensions
• Quantum Phase Transition in Frustrated Two-Dimensional Antiferromagnets
• Instantaneous Spin Correlations in La2CuO4
• The massive $C{P}^{N-1}$ model for frustrated spin systems
• Spin-stiffness and topological defects in two-dimensional frustrated spin systems

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• {23}Na nuclear spin-lattice relaxation studies of Na2Ni2TeO6
• Nonequilibrium relaxation study of the anisotropic antiferromagnetic Heisenberg model on the triangular lattice
• Magnetic order, spin waves and fluctuations in the triangular antiferromagnet La2Ca2MnO7
• 7Li NMR Studies of LiCrO2