Spin-1/2 Heisenberg antiferromagnet on the kagome ´ lattice: High-temperature expansion and exact-diagonalization studies
Spin-1/2 Heisenberg antiferromagnet on the kagome ´ lattice: High-temperature expansion and exact-diagonalization studies
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kagome´晶格上的自旋1/2海森堡反铁磁体：高温膨胀和精确对角化研究
DOI：
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发表时间：
1994
期刊：
影响因子：
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通讯作者：
A. P. Young
中科院分区：
文献类型：
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作者：
N. Elstner;A. P. Young
对于自旋为1/2的海森堡反铁磁体，我们计算了高温比热和结构因子。与精确对角化研究的系列比较表明，比热在较低温度下具有进一步的结构，除了在Tensuremath{approxeq}2/3处的高温峰。在T=0.25的结构因子同意相当不错的结果与基态的有限集群与36个网站。在这个温度下，结构因子小于其T=ensuremath{infty}值的两倍，并且仅微弱地依赖于波矢量q，这表明没有磁序和小于一个晶格间距的相关长度。均匀磁化率在Tensuremath{approxeq}1/6处具有最大值，并且在较低温度下呈指数消失。
For the spin-1/2 Heisenberg antiferromagnet on the kagom'e lattice we calculate the high-temperature series for the specific heat and the structure factor. A comparison of the series with exact-diagonalization studies shows that the specific heat has further structure at lower temperature in addition to a high-temperature peak at Tensuremath{approxeq}2/3. At T=0.25 the structure factor agrees quite well with results for the ground state of a finite cluster with 36 sites. At this temperature the structure factor is less than two times its T=ensuremath{infty} value and depends only weakly on the wave vector q, indicating the absence of magnetic order and a correlation length of less than one lattice spacing. The uniform susceptibility has a maximum at Tensuremath{approxeq}1/6 and vanishes exponentially for lower temperatures.