Monte Carlo study of doping change and disorder effect on double-exchange ferromagnetism
Monte Carlo study of doping change and disorder effect on double-exchange ferromagnetism
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双交换铁磁性掺杂变化和无序效应的蒙特卡罗研究
DOI：
10.1103/physrevb.68.144432
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发表时间：
2003
影响因子：
3.7
通讯作者：
N. Furukawa
中科院分区：
文献类型：
--
作者：
Y. Motome;N. Furukawa
研究了有和没有淬火无序的三维双交换模型的相图和临界性质。采用蒙特卡罗方法和对有限尺寸效应的系统分析，我们估计了居里温度和临界指数作为掺杂浓度和随机势强度的函数。正如这种动力学驱动的铁磁性所预期的那样，居里温度与基态电子的动能成正比。这种转变的普遍性类由短程海森堡不动点描述。结果与巨磁阻锰氧化物的实验结果进行了比较。
Phase diagram and critical properties are studied for three-dimensional double-exchange model with and without quenched disorder. Employing the Monte Carlo method and the systematic analysis on the finite-size effect, we estimate the Curie temperature and the critical exponent as functions of the doping concentration and the strength of the random potential. The Curie temperature well scales to the kinetic energy of electrons in the ground state as expected for this kinetics-driven ferromagnetism. The universality class of this transition is described by the short-range Heisenberg fixed point. The results are compared with experimental results in the colossal magnetoresistance manganites.