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^{63}Cu, ^{35}Cl, and ^{1}H NMR in the S=1/2 Kagomé Lattice ZnCu_{3}(OH)_{6}Cl_{2}

T. Imai·E. A. Nytko·B. M. Bartlett·M. P. Shores·D. G. Nocera
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Abstract

ZnCu$_{3}$(OH)$_{6}$Cl$_{2}$ ($S=1/2$) is a promising new candidate for an ideal Kagomé Heisenberg antiferromagnet, because there is no magnetic phase transition down to $\sim$50 mK. We investigated its local magnetic and lattice environments with NMR techniques. We demonstrate that the intrinsic local spin susceptibility {\it decreases} toward T=0, but that slow freezing of the lattice near $\sim$50 K, presumably associated with OH bonds, contributes to a large increase of local spin susceptibility and its distribution. Spin dynamics near T=0 obey a power-law behavior in high magnetic fields.

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T. Imai, E. A. Nytko, B. M. Bartlett, M. P. Shores, D. G. Nocera. 2008-01-11. ^{63}Cu, ^{35}Cl, and ^{1}H NMR in the S=1/2 Kagomé Lattice ZnCu_{3}(OH)_{6}Cl_{2}. https://doi.org/10.1103/physrevlett.100.077203

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