磁各向异性对二维人工室温斯格米子（skyrmions）的拓扑性质调制及其机理研究

利用磁各向异性能、退磁能、海森堡相互作用能的相互竞争可替代DM相互作用，导致斯格米子（skyrmion）基态自发产生的思想，以具有面外磁化背景与磁涡旋组合的单晶多层膜，具有不同纳米构型的单晶多层膜为基础，采用分子束外延技术与纳米加工技术制备室温下人工skyrmion，确定室温下skyrmion稳定存在的薄膜厚度与尺寸范围。通过引入原子台阶、界面粗糙度与界面应力等结构因素调制所制备磁性薄膜的磁各向异性。深入研究磁各向异性变化对skyrmion的产生、稳定性、拓扑性质的影响规律。进一步深入研究引入磁场、电场以及电磁场等条件下，磁各向异性变化对skyrmion动力学行为的影响规律。通过比较实验结果与微磁学模拟结果，从能量竞争平衡的角度，建立描述skyrmion运动的唯象模型，揭示磁各向异性调制skyrmion拓扑性质的物理机理，为skyrmion实现人工可控，最终走向应用提供理论与实验指导。

The skyrmion ground state could be produced when the Dzyaloshinsky-Moriya (DM) interaction equal to the energy competition effect from three energy that are magnetic anisotropy energy, demagnetized energy and Heisenberg interaction energy respectively. Under this proposal, we try to prepare the artificial skyrmion by using molecular beam epitaxy technique to prepare magnetic multiplayer system with out-of-plane magnetization and vortex, and the multiplayer system with different nanopatterns. The critical thickness and size range for the existence of skyrmion will be investigated. The influences on the production, stabilization, and topological properties of the artificial skyrmion will be investigated by modulating magnetic anisotropy of the magnetic film through changing the atomic step intensity of the substrate, the roughness and stress on the interface between the film and substrate. In further, we will investigate the correlation between the anisotropy and the dynamics behavior of skyrmion under different fields, such as a static magnetic field, an impulse magnetic field, an electric field and an electromagnetic field. The micromagnetic simulation will be also executed to be used to compare with the experimental results which will help to construct the phenomenological model. We hope that the present proposal could help to deeply understand the essence of skyrmion and supply the experimental and theoretical guide for its application in the future intelligent material industry.