反铁磁和铁磁是两种基本磁结构。对于反铁磁磁畴结构的研究，不但有助于深入理解反铁磁自旋相互作用，也决定了反铁磁材料在自旋电子学器件中的应用能力。反铁磁自旋电子学的发展需要在磁场和电场作用下原位实时测量反铁磁磁畴结构及演化。申请人最近发展了一种基于Voigt效应的光学显微测量反铁磁磁畴的新方法。本项目申请利用光学显微探测反铁磁磁畴及其在外场下的演化，主要内容包括： (1)利用光学显微镜技术研究高质量单晶反铁磁薄膜中反铁磁磁畴随着厚度、生长条件和各向异性的变化，以及横向尺寸对反铁磁磁畴的调控；(2)在铁磁/反铁磁异质结构中，研究界面交换耦合导致的反铁磁磁畴的动力演变过程，通过研究磁畴微结构的动态变化来理解交换耦合的物理机制，探索磁场作用下的反铁磁磁畴壁运动规律；(3)在微纳结构中研究反铁磁磁畴在电流脉冲下的演化行为，探索电流调控反铁磁磁畴的有效方法，促进反铁磁自旋电子学的发展。

Antiferromagnet and ferromagnet are two fundamental magnetic structures. The studies on antiferromagnetic (AFM) domain structure, will not only help understanding the interactions between AFM spins, but also influence the device applications of AFM materials in spintronics. The development of AFM spintronics requires the abilities of in-situ studying the AFM domains under magnetic or electric fields. We recently developed a new method to detect the AFM domains with optical microscope based on Voigt effect, and propose to study the AFM domains and its evolutions under external field with optical microscope. The outline of this proposed study is described as: 1) we will prepare high quality single-crystalline AFM thin films, and use the optical microscope to study the dependence of AFM domains on film thickness, the preparation condition and AFM anisotropy. Moreover, we will study the AFM domain properties due to lateral confinement in the AFM microstructures. 2) In FM/AFM heterostructures, we will study the real-time dynamical evolution of AFM domains due to interfacial exchange coupling under external magnetic field, and try to further understand the physical mechanism of exchange coupling by measuring the FM and AFM domains simultaneously. We will further explore the phenomena of AFM domain wall motion driven by magnetic field or the effective field due to the interface exchange coupling. 3) We will study the real-time evolution of AFM domains excited by the electric current pulse in the patterned AFM nanostructures, and explore the effective method to manipulate the AFM domains with the electric current, which will promote the development of AFM spintronics.