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arXiv · 1106.6309

Spin Liquid Ground State in the Frustrated Kagome Antiferromagnet MgCu3(OH)6Cl2

E. Kermarrec·P. Mendels·F. Bert·R. H. Colman·A. S. Wills·P. Strobel·P. Bonville·A. Hillier·A. Amato
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Abstract

We report muSR experiments on Mg{x}Cu{4-x}(OH)6Cl2 with x \sim 1, a new material isostructural to Herbertsmithite exhibiting regular kagome planes of spin 1/2 (Cu^{2+}), and therefore a candidate for a spin liquid ground state. We evidence the absence of any magnetic ordering down to 20 mK (\sim J/10^4). We investigate in detail the spin dynamics on well characterized samples in zero and applied longitudinal fields and propose a low T defect based interpretation to explain the unconventional dynamics observed in the quantum spin liquid phase.

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E. Kermarrec, P. Mendels, F. Bert, R. H. Colman, A. S. Wills, P. Strobel, P. Bonville, A. Hillier, A. Amato. 2011-06-30. Spin Liquid Ground State in the Frustrated Kagome Antiferromagnet MgCu3(OH)6Cl2. https://doi.org/10.1103/physrevb.84.100401

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