报告题目: Inhomogeneous strain induced Observation of non-linear spin textures in manganite thin films and one dimensional wire

报告人：Dr. Malik（武汉大学物理科学与技术学院）

报告时间：2023年4月12日（周三）上午10:20

报告地点：文理学部教四4-201

报告摘要:

Mixed-valance manganites with strong electron correlation exhibit strong potential for spintronics, where emergent magnetic behaviors, such as propagation of high-frequency spin waves and giant topological Hall Effects can be driven by their mesoscale spin textures. Here, we create magnetic vortex clusters with flux closure spin configurations in single-crystal La_0.67Sr_0.33MnO₃ wire. A distinctive transformation from out-of-plane domains to a vortex state is directly visualized using magnetic force microscopy at 4 K in wires when the width is below 1.0 μm. The phase-field modeling indicates that the inhomogeneous strain, accompanying with shape anisotropy, plays a key role for stabilizing the flux-closure spin structure. Also an emergent Dzyaloshinskii-Moriya interaction (DMI) can be achieved in a La_0.67Sr_0.33MnO₃, by a strain. This strain-driven DMI brings robust room-temperature magnetic skyrmion lattice as well as a spiral lattice at zero magnetic field. Magnetic force microscopy (MFM) from attocube Scanning probe microscopy (AttoSPM) was utilized to study direct observation of magnetic domain and its control with external magnetic field. AttoSPM is promising and powerful tool to study magnetic domains under extreme conditions (~9T and 1.8K~300K).

报告人简介：

Dr. Malik from Pakistan is currently working as a postdoc fellow at School of Physics and Technology, Wuhan University. He obtained his Ph.D. in Condensed Matter Physics, from Beijing Normal University, Beijing, China in January 2020 and Undergraduate from University of Sargodha, Pakistan in 2012. Before perusing his PhD he worked as a High School Teacher in Government School of his hometown and a year as Assistant professor of Physics in University of Mianwali Pakistan after Ph.D.

During his Ph.D. he focused on observation and manipulation of magnetic spin structures in complex oxide ferromagnetic thin films and nanostructures for the application of spintronic devices. His research focuses on the artificial design of oxide-based and 2D materials based building blocks (Domains, domain walls, non-linear spin structures), especially in ferromagnetic materials.

邀请人：于霆 教授