Spin-splitting in Bent Graphene Nanoribbon studied by Generalized Bloch Theorem: A New Mechanism towards Half-Metallicity

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讲座内容：

Often, low dimensional systems such as graphene are of superior structural flexibility and exhibit excellent electromechanical response, i.e., the coupling of electronic properties with structural deformation. This indicates that novel electronic properties can be obtained by strain manipulation on electronic states. The relevant studies have led to an emergent area, i.e., strain engineering. However, theoretical research such as first-principles calculation mainly focuses on homogeneous strain and the exploration of inhomogeneous strain is rare. Largely, this is because that inhomogeneous strain destroys the translational symmetry of crystal, which the traditional approaches of electronic energy band calculations rely on. We developed a new approach of energy band calculation named as Generalized Bloch Theorem, coupled with self-consistent charge density-functional tight-binding. This new approach can effectively deal with low dimensional materials under torsional or bending deformations. As an example, we show that a simple in-plane bending can induce spin-splitting in zigzag graphene nanoribbons and eventually results in the highly desired half-metallic phase.

主讲人介绍：

张东波，现任北京计算科学研究中心特聘研究员。2002年7月本科毕业于北京科技大学，2010年11月获美国明尼苏达大学 • 双城分校材料学博士学位。随后在美国明尼苏达大学机械工程系、美国明尼苏达大学化工与材料系作博士后等研究工作。2013年入选国家青年千人计划。主要的研究方向包括：计算凝聚态物理、第一性原理分子动力学；紧束缚分子动力学、以广义布洛赫方法为基础的低维电子结构计算、与声子非谐相关的热力学计算、固态材料热输运理论与计算方法等。

发布时间：2017-05-17 15:11:08