Spin-wave excitations and perpendicular susceptibility of a diluted antiferromagnet near percolation threshold.
Spin-wave excitations and perpendicular susceptibility of a diluted antiferromagnet near percolation threshold.
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稀释反铁磁体在渗透阈值附近的自旋波激发和垂直磁化率。
DOI：
10.1103/physrevb.32.3251
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发表时间：
1985
期刊：
影响因子：
--
通讯作者：
Harris
中科院分区：
文献类型：
--
作者：
Kumar;Harris
研究了在逾渗阈值pc附近稀释反铁磁体的长波激发。在流体动力学理论中，激励频率取决于两个参数A和χ t。A是与交错磁化的空间变化相关的刚度，χ t是反铁磁体有序状态下的垂直磁化率。A在pc附近的临界行为是已知的。我们发展了一种场论形式来计算χ t。我们在平均场近似下计算χ t，发现它发散为||ln（p-pc）||当浓度P接近Pc时，一些进一步的标度参数产生了一个标度关系，该关系将χ t的发散指数与渗流临界点处的其他已知指数联系起来。
The long-wavelength excitations of a diluted antiferromagnet near the percolation threshold p c are studied. Within the hydrodynamic theory, the excitation frequency depends on two parameters, A and χ t . A is the stiffness associated with the spatial variation in the staggered magnetization and χ t is the perpendicular susceptibility in the ordered state of the antiferromagnet. The critical behavior of A near p c is known. We develop a field-theoretic formalism to calculate χ t . We ex- plicitly calculate χ t in the mean-field approximation and find that it diverges as ||ln(p-p c )||, as the concentration p approaches p c . Some further scaling arguments yield a scaling relation relating the divergence exponent of χ t with other known exponents at the percolation critical point.