摘要
用统计力学及MonteCarlo方法分别处理和模拟了单粒子自旋和团簇自旋点阵下的经典Heisenberg模型 .主要结果如下 :①比较常规大块状单自旋态 ,纳米团簇自旋态组成的超顺磁体系具有增强磁热熵效应 .②在纳米尺度存在一最佳团簇尺寸 。
The peculiar magnetic behavior of nano magnetic system was investigated by both statistical physics and Monte Carlo simulation to classical Heisenberg model on single spin as well as cluster spins lattice with periodic boundary condition (PBC). Simulation results can be summarized into two major findings. Firstly, superparamagnetic system comprised of cluster spins has an enhanced magnetic entropy change Δ S over that of single spin system. Secondly, there exists an optimal cluster size corresponding to the peak in the Δ S versus cluster size curve.
出处
《中山大学学报（自然科学版）》
CAS
CSCD
北大核心
2000年第3期30-34,共5页
Acta Scientiarum Naturalium Universitatis Sunyatseni
基金
国家自然科学基金资助项目!(5970 2 0 0 4 )
关键词
纳米团簇
纳米磁性体系
蒙特卡罗模拟
统计力学
nano cluster
Heisenberg model
Monte Carlo simulation
superferromagnetism/superparamagnetism
