Field-Induced Freezing of a Quantum Spin Liquid on the Kagome Lattice
Field-Induced Freezing of a Quantum Spin Liquid on the Kagome Lattice
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DOI：
10.1103/physrevlett.107.237201
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发表时间：
2011-11-28
影响因子：
8.6
通讯作者：
Harrison, A.
中科院分区：
文献类型：
--
作者：
Jeong, M.;Bert, F.;Harrison, A.
本文报道了S = 12（Cu ~（2+））kagome反铁磁体Herbertsmithite ZnCu_3（OH）（6）Cl ~（2-）在2 ~ 12 T磁场下的~（17）O NMR测量结果。虽然Herbertsmithite在零场下显示出无带隙的自旋液体行为，但我们发现在亚开尔文温度下由外加磁场引起的自旋固相不稳定性。后一阶段显示出很大程度上抑制的时刻小于或类似于0.1 μ（B）和间隙的激励。H-T相图表明在小而有限的磁场μ H-0（c）= 1.55（25）T处存在量子临界点。我们讨论了这一发现的光的微扰Dzyaloshinskiii-Moriya相互作用，理论上提出了维持量子临界制度的量子戈薇海森堡反铁磁模型。
We report O-17 NMR measurements in the S = 1/2 (Cu2+) kagome antiferromagnet Herbertsmithite ZnCu3(OH)(6)Cl-2 down to 45 mK in magnetic fields ranging from 2 to 12 T. 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 less than or similar to 0.1 mu(B) and gapped excitations. The H - T phase diagram suggests the existence of a quantum critical point at the small but finite magnetic field mu H-0(c) = 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.