低维螺旋磁体中Skyrmions相自旋转移矩效应以及电子输运特性研究

项目名称： 低维螺旋磁体中Skyrmions相自旋转移矩效应以及电子输运特性研究

项目编号： No.11474290

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 杜海峰

作者单位： 中国科学院合肥物质科学研究院

项目金额： 90万元

中文摘要： 自旋极化电流是对磁性材料的自旋动力学行为进行有效调控的重要手段之一。然而在传统的磁性材料中，诱导磁性介质磁化反转或磁畴运动需要高的电流密度，易产生大的焦耳热，实际上阻碍了自旋转移矩效应的广泛应用。螺旋磁体中拓扑稳定的磁结构Skyrmions相的出现为解决相关器件的焦耳热问题带来了新的契机。一方面，一个非常小的电流密度即可驱动螺旋磁体中Skyrmions运动；另一方面，螺旋磁体中丰富的非共线磁结构有可能在低维螺旋磁体中实现超导与铁磁共存，从而构建低能耗的超电流自旋电子学器件。本项目即以低维螺旋磁体MnSi纳米线、纳米条带为研究对象，以前期的工作积累为基础，前瞻性的开展空间受限对螺旋磁体中Skyrmions态的自旋转移矩效应的影响,以及一维螺旋磁体纳米线与超导体之间近邻效应的研究。相关的成果将加深和丰富人们对低维螺旋磁体的认识,并将为未来开发新型量子器件提供重要的实验依据。

中文关键词： 螺旋磁体；Skyrmions；超导；一维纳米结构

英文摘要： Spin polarized current is one of the most efficient methods that control the spin dynamics in magnetic materials. However, it generates large ohmic heating due to the high current density required to move the domain walls of ferromagnetic materials. Which undoubtedly limited its real application. More recently, a novel type of topologically stable vortex-like spin textures, called skyrmions, have been discovered in helimagnets, which might prove new opportunity to solve the ohmic heating effect. One of its prominent features is that the threshold current density to move a skyrmion is much smaller than the current density required to move the domain walls in ferromagnetic materials. On the other hand, the rich non-collinear spin textures in helimagnets might combine the zero-resistance supercurrent of superconductors with the ferromagnets, further building the no-ohmic heating superconducting spintronics device. In this project, based on our previous work, we attempt to study the effect of spatial confinement on the spin transfer torque in low dimensional helimagnets, especially nanowires and nano stripe, and the interaction between superconductor and helimagnetic nanowires.The proposed work is expected to shed new light on the nature of low-dimensional helimagnets,further provide chance of exploring new quantum devices based on skyrmions materials.

英文关键词： helimagnets;Skyrmions;superconductor;1D nanostructure