<注：本视频仅用于学术交流，版权归报告人所有>
►【“凝聚态物理-中关村论坛”第371次讲座】
报告题目：Recent progresses in realization of topological states in graphene and its derivatives
报 告 人：Prof. Xiao HU
International Center for Materials Nanoarchitectonics (WPI-MANA)
National Institute for Materials Science (NIMS), Tsukuba, Japan
报告时间：2019年9月19日（星期四）下午16:00
报告地点：中科院物理研究所M楼236会议室
报告人简介：
胡晓，东京大学理学博士，世界顶级计划材料纳米结构学研究中心（WPI-MANA）首席科学家，日本科学技术振兴机构（JST）拓扑顶峰计划（CREST Topology）首席专家，筑波大学教授。胡晓教授从事理论物理研究，曾先后在日本东京大学、东北大学、美国国家标准技术研究所(NIST)等研究机构从事教学科研工作。1996年加盟日本国立物质材料研究机构，担任研究主管。他在铜氧化物高温超导Abrikosov磁通格子的融化相变和动力学相变，本征约瑟夫森结THz电磁波辐射，新奇拓扑态及物质设计等研究领域取得了一系列重要成果。至今已在Superconductor Science and Technology、Advanced Materials、Advances in Physics等世界顶级期刊发表综述文章。
报告摘要：
Honeycomb lattice has played an extremely important role in fostering the concept of topology with the renowned Haldane model and Kane-Mele model as the icons [1]. We have found another method to generate topological states based on graphene and artificial graphenes where only nearest-neighbor hoppings are considered [2]. The topology with time-reversal symmetry has its root in the Dirac-type linear dispersion provided by the honeycomb structure, and is induced by a short-range texture respecting C6v symmetry, which opens a bandgap accompanied by a p-d band inversion. The orbital angular momentum carried by the p and d orbitals accommodated in the hexagonal unit cell plays the role of pseudospin, and the topological edge state with pseudospin-momentum locking is an analogue of the helical edge state in quantum spin Hall insulators. I will explain recent theoretical and experimental progresses in realizing topological photonic and electronic states based on this scheme [3, 4].
XH is supported by CREST (JPMJCR18T4, JST) and KAKENHI (17H02913, JSPS).
References:
[1] H.-M. Weng, R. Yu, X. Hu, X. Dai and Z. Fang, Adv. Phys. 64, 227 (2015).
[2] L.-H. Wu and X. Hu, Phys. Rev. Lett. 114, 223901 (2015).
[3] Y.-T. Yang, X. Hu and Z.-H. Hang et al., Phys. Rev. Lett. 120, 217401 (2018).
[4] Y. Li, H. Chen and X. Hu et al., Nat. Commun. 9, 4598 (2018).