MnNiGa合金/压电陶瓷多铁异质结制备及其拓扑磁畴的电场调控

The project intends to manipulate the evolution of magnetic skyrmions in metals by using electric field based on a design of heterostructure. Such a heterostructure consists of piezoelectric ceramics and MnNiGa single crystal that is reported to host high-temperature stability skyrmions in our previous work. One of the research targets of this project is to solve a key scientific problem that the correlation and regulation among electric field, magnetocrystalline anisotropy, magnetic exchange coupling effect, and the evolution of magnetic skymions. Another one is to construct the relationship between the electric field and the nucleation barrier of magnetic skyrmions in the MnNiGa single crystal, by utilizing electric-field in-situ magnetotransport measurements, electric-field in-situ magnetic force microscope (MFM) and micromagnetic simulation. On the other hand, the intrinsic physical mechanism for controlling of the evolution of magnetic skyrmions by electric field is further studied. The ultimate goal of this project is to construct a theoretical model for electronically controlling the evolution of magnetic skyrmions, which are of great significance for future practical application of magnetic skyrmions.

电场调控磁斯格明子具有发热小、调控自由度高等优点，非常有利于发展小型化、集成化和低能耗的磁斯格明子电子学器件，受到了国内外学者的广泛关注。现阶段电场调控磁斯格明子方面的研究主要集中于氧化物单晶或具有氧化物-金属界面的薄膜。然而，现有方法对广泛存在磁斯格明子的金属材料并不适用。基于此研究背景，本项目拟采用固相粘结工艺，将我们前期工作中发现的具有宽温区、跨室温磁斯格明子存在的MnNiGa合金单晶与压电陶瓷复合制成多铁异质结，并以此为研究对象，围绕电场、磁晶各向异性、磁交换作用与磁斯格明子拓扑磁畴演化之间的关联与调控这一关键科学问题，结合电场原位磁输运测量技术、电场原位磁力显微镜观测技术、微磁学模拟，建立电场与MnNiGa合金中磁斯格明子成核势垒之间的联系，并进一步阐述电场调控磁斯格明子拓扑磁畴演化的内在物理机制，最终建立电控磁斯格明子的理论框架，推动磁斯格明子实用化。

在本项目支持下，我们制备出了MnNiGa单晶/PMNPT和[Pt/Co/Ta]12多层薄膜/PMNPT两类多铁异质结，并以此为研究对象，围绕电场、磁晶各向异性、磁交换作用与磁斯格明子拓扑磁畴演化之间的关联与调控这一关键科学问题，结合电场原位磁输运测量技术、电场原位磁力显微镜观测技术、微磁学模拟，建立了电场与MnNiGa合金中磁斯格明子成核势垒之间的联系，并进一步阐明了电场调控磁斯格明子拓扑磁畴演化的内在物理机制，建立了电场调控磁斯格明子的理论框架，推动了磁斯格明子实用化。