钆单晶磁化曲线的微磁学模拟

Micromagnetic Simulation of Magnetization Curve of Gadolinium Single Crystal

HCP结构的钆单晶是一种典型稀土永磁材料,其居里温度在室温附近,作为一种良好的单质磁制冷材料,近年来得到广泛关注。利用原子尺度的有效自旋哈密顿量,通过使用混合蒙特卡罗方法的微磁学模拟研究,得到了钆单晶的磁化曲线,与实验结果吻合良好。磁化曲线的获得,不仅为居里温度附近的实验提供理论依据,也有助于进一步研究钆单晶的交换作用系数、各项异性常数等随温度变化行为的磁学性质。

Gadolinium single crystal with HCP structure is a kind of rare earth permanent magnetic material.Nearing the room temperature of its Curie temperature makes it a good material for single substance magnetic refrigeration and has become hot spot of the research area in recent years.In this paper,we studied the magnetization of Gd single crystal and obtained the magnetization curve through micromagnetic simulation by using the hybrid Monte Carlo method according the effective spin Hamiltonian at the atomic scale.The magnetization curve was in good agreement with the experimental results.The successful simulation of the magnetization curve not only provides a theoretical basis for the experiment near the Curie temperature,but also facilitates the further study of some magnetic properties of gadolinium single crystal,such as the behavior of exchange interaction coefficient and anisotropy constant with temperature.