Magnetic ground state of an experimental S=1/2 kagome antiferromagnet.
Magnetic ground state of an experimental S=1/2 kagome antiferromagnet.
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DOI：
10.1103/physrevlett.100.157205
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发表时间：
2007-05
影响因子：
8.6
通讯作者：
M. A. D. Vries;Konstantin V. Kamenev;W. Kockelmann;Javier Sanchez-Benitez;A. Harrison
中科院分区：
文献类型：
--
作者：
M. A. D. Vries;Konstantin V. Kamenev;W. Kockelmann;Javier Sanchez-Benitez;A. Harrison
我们对近乎完美的 S=1/2 kagome 反铁磁体、锌副氯铜矿 Zn(x)Cu(4-x)(OH)(6)Cl(2) 的热容进行了详细分析，作为化学计量 x-->1 和高达 9 T 场的函数。我们通过考虑弱 Cu2+/Zn2+ 交换获得了 kagome 层固有的热容 在 Cu 和 Zn 位点之间，这是使用中子衍射在 x=1 时独立测量的。 x=0.8...1 时热容的演变与磁化率的磁滞有关。我们得出的结论是，当 x>0.8 时，副氯铜矿锌是一种没有自旋间隙的自旋液体，其中不成对的自旋会产生宏观简并的基态流形，随着 x 的降低，其玻璃态动力学逐渐增强。
We present a detailed analysis of the heat capacity of a near-perfect S=1/2 kagome antiferromagnet, zinc paratacamite Zn(x)Cu(4-x)(OH)(6)Cl(2), as a function of stoichiometry x-->1 and for fields of up to 9 T. We obtain the heat capacity intrinsic to the kagome layers by accounting for the weak Cu2+/Zn2+ exchange between the Cu and the Zn sites, which was measured independently for x=1 using neutron diffraction. The evolution of the heat capacity for x=0.8...1 is then related to the hysteresis in the magnetic susceptibility. We conclude that for x>0.8 zinc paratacamite is a spin liquid without a spin gap, in which unpaired spins give rise to a macroscopically degenerate ground state manifold with increasingly glassy dynamics as x is lowered.