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Quantum magnetism in the paratacamite family: towards an ideal kagome lattice

P. Mendels·F. Bert·M. A. de Vries·A. Olariu·A. Harrison·F. Duc·J. C. Trombe·J. Lord·A. Amato·C. Baines
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Abstract

We report MuSR measurements on the S=1/2 (Cu2+) paratacamite Zn_xCu_{4-x}(OH)_6Cl_2 family. Despite a Weiss temperature of -300 K, the x=1 compound is found to have no transition to a magnetic frozen state down to 50 mK as theoretically expected for the kagome Heisenberg antiferromagnet. We find that the limit between a dynamical and a frozen inhomogeneous ground state occurs around x=0.5. For x=1, we discuss the relevance to a singlet picture.

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P. Mendels, F. Bert, M. A. de Vries, A. Olariu, A. Harrison, F. Duc, J. C. Trombe, J. Lord, A. Amato, C. Baines. 2007-02-26. Quantum magnetism in the paratacamite family: towards an ideal kagome lattice. https://doi.org/10.1103/physrevlett.98.077204

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