表面装饰类石墨烯纳米粒子的磁性  

Magnetic properties of surface-decorated graphene-like nanoparticles

作　　者：秦伟凡 吴闯 姜伟[1] QIN Weifan;WU Chuang;JIANG Wei(School of Science,Shenyang University of Technology,Shenyang 110870,China;Experimental Teaching Center,Shenyang Normal University,Shenyang 110034,China)

机构地区：[1]沈阳工业大学理学院,沈阳110870 [2]沈阳师范大学实验教学中心,沈阳110034

出　　处：《沈阳师范大学学报（自然科学版）》2023年第3期268-273,共6页Journal of Shenyang Normal University:Natural Science Edition

基　　金：辽宁省教育厅科学研究经费项目(LJKZ1004)。

摘　　要：为了研究交换作用对表面装饰类石墨烯纳米粒子的磁性影响,从微观量子角度对表面装饰类石墨烯纳米粒子建立Ising模型,写出描述系统的哈密顿量。基于蒙特卡洛模拟方法,研究了粒子内部铁磁交换作用和表面亚铁磁交换作用对系统的磁矩、磁化率、阻碍温度和阶梯效应的影响。数值计算结果表明,交换作用对系统磁性具有重要影响,在外场作用下,磁化曲线随温度的增加趋于一个稳定值,磁矩和磁化率曲线均会出现峰值现象,磁化率峰值对应的阻碍温度随交换作用增加而增大。此外,多重磁化平台现象也被发现,饱和磁矩对应的饱和磁场随交换作用增加而增大。这些结果对该类材料在自旋电子器件中的潜在应用具有指导意义。To study the effects of exchange couplings on the magnetic properties of surface-decorated graphene-like nanoparticles,from the microscopic quantum point of view,Ising model of surface-decorated graphene-like nanoparticles was established,and the Hamiltonian described for the system was written.Based on Monte Carlo simulation,the influences of internal ferromagnetic exchange and surface decoration ferrimagnetic exchange on the magnetization,the susceptibility,the block temperature and the magnetization plateau have been studied in detail.The numerical results showed the exchange couplings have important roles in surface-decorated graphene-like nanoparticles.All magnetization curves approach to keep a value with increasing temperature in the extern magnetic filed.It is a peak phenomenon on the magnetization and susceptibility curves.The blocking temperature corresponding to the peak of susceptibility increased with increasing.In additional,multiple magnetization plateaus were found,the saturation magnetic filed increased with increasing.These results of such nano-materials are useful for the potential applications in spintronic devices.

关 键 词：表面装饰 类石墨烯纳米粒子 蒙特卡洛模拟 磁矩 磁化率 阶梯效应 

分 类 号：TG[金属学及工艺]