人工反铁磁耦合多层膜中的自旋轨道扭矩翻转机制及磁相互作用研究

The synthetic antiferromagnetic(SAF) stacks, which consist of ferromagnetic layer(FM)/insert layer(IL)/exchange coupling layer/IL/FM, are deposited by magnetron sputtering. Patterned by photolithography and ion milling, the samples are driven by current and magnetic field and characterized by physical property measurement system(PPMS) and magneto-optic Kerr effect microscope(MOKE). Utilizing effective field induced by exchange bias, we try to cancel the static applied field needed for switching the SAF magnetization by current, and understand the mechanism of influence to domain creation and movement by SAF coupling and exchange bias. By changing component and thickness of FM and IL layers, we adjust and control anisotropy, DM interaction and spin orbit torque of two FM layers separately in order to research the interaction between DM interaction and SAF coupling. At last we will combine the experimental results with micro-magnetic simulation to investigate the mechanism of domain structure formed by interface and interlayer coupling, shedding a light on nature of spin-orbit coupling and exchange coupling, meanwhile take a step forward to practical spin-orbit torque device and SAF skyrmion structure.

采用磁控溅射方法生长铁磁层/插层/耦合层/插层/铁磁层型人工反铁磁耦合结构，使用光刻技术和离子刻蚀技术制备器件，并用物性测量系统（PPMS）和磁光克尔效应（MOKE）显微镜研究电流磁场对磁畴的翻转和驱动。在人工反铁磁结构中通过交换偏置引入等效场，实现人工反铁磁结构中无外磁场的电致翻转，研究交换偏置和反铁磁耦合对磁畴形核、畴壁移动影响的机制。通过改变铁磁层和插层的成分和厚度独立地调控两个铁磁层的各向异性、DM相互作用以及自旋轨道扭矩，通过观察磁畴的运动研究DM相互作用和反铁磁交换耦合相互影响的机制。 结合实验观察和微磁学模拟，理解界面和层间耦合影响磁畴结构的机制，为进一步认清自旋轨道耦合和层间交换耦合的本质提供科学依据，同时也为自旋轨道扭矩型器件的实用化以及实现反铁磁型斯格明子（Skyrmion）结构提供有效指导。

采用磁控溅射方法生长铁磁层/插层/耦合层/插层/铁磁层型人工反铁磁耦合结构，使用光刻技术和离子刻蚀技术制备器件，并用物性测量系统（PPMS）和磁光克尔效应（MOKE）显微镜研究电流磁场对磁畴的翻转和驱动。在人工反铁磁结构中通过交换偏置引入等效场，实现人工反铁磁结构中无外磁场的电致翻转，研究交换偏置和反铁磁耦合对磁畴形核，畴壁移动影响的机制。通过改变铁磁层和插层的成分和厚度独立地调控两个铁磁层的各向异性、DM相互作用以及自旋轨道扭矩，通过观察磁畴的运动研究DM相互作用和反铁磁交换耦合相互影响的机制。 结合实验观察和微磁学模拟，理解界面和层间耦合影响磁畴结构的机制，为进一步认清自旋轨道耦合和层间交换耦合的本质提供科学依据，同时也为自旋轨道扭矩型器件的实用化以及实现反铁磁型斯格明子（Skyrmion）结构提供有效指导。