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arXiv · 1109.1316

Field-Induced Freezing of a Quantum Spin Liquid on the Kagome Lattice

Abstract

We report 17O NMR measurements in the S=1/2 Cu2+ kagome antiferromagnet Herbertsmithite ZnCu3(OH)6Cl2 down to 45mK in magnetic fields ranging from 2T to 12T. While Herbertsmithite displays a gapless spin-liquid behavior in zero field, we uncover an instability toward a spin-solid phase at sub-kelvin temperature induced by an applied magnetic field. The latter phase shows largely suppressed moments $\lesssim 0.1\muB$ and gapped excitations. The H-T phase diagram suggests the existence of a quantum critical point at the small but finite magnetic field mu0 Hc=1.55(25)T. We discuss this finding in light of the perturbative Dzyaloshinskii-Moriya interaction which was theoretically proposed to sustain a quantum critical regime for the quantum kagome Heisenberg antiferromagnet model.

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BibTeXRIS

M. Jeong, F. Bert, P. Mendels, F. Duc, J. C. Trombe, M. A. de Vries, A. Harrison. 2011-09-06. Field-Induced Freezing of a Quantum Spin Liquid on the Kagome Lattice. https://doi.org/10.1103/physrevlett.107.237201

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