On October 22nd, On-chip Valley Topological Materials for Elastic Wave is published online in Nature Materials A study of manipulation of on-chip valley topological materials for elastic wave manipulation. Authors: Mian Yan, Jiuyang Lu, Feng Li, Weiyin Deng, Xueqin Huang, Jiahong Ma and Zhengyou Liu. Among them, 2016 doctoral student Yan Mou, Associate Professor Lu Jiuyang and Professor Li Feng from school of Physics and Optoelectronics, SOUTH China University of Technology are the co-first authors. The first signing unit of this paper is South China University of Technology.

Screenshot of the paper website

  Valley of energy refers to the extreme point of energy band in momentum space. As it appears in pairs, it can be regarded as pseudospin and can be used as a new degree of freedom to control electron transport operation, which has important application prospects. With the rapid development of valley electronics, the study of valley state of electromagnetic wave and acoustic wave has attracted great attention.

  The team of Yan, Lu, and Li prepared valley topological materials for elastic wave manipulation on silicon wafers using a carefully designed microfabrication process (figure A). Theoretical and experimental results show that the elastic wave can be transmitted on the chip in the form of edge state with low loss along the designed path (FIG. B).

Figure (a) : silicon topological material and magnified photo; (b) and (c) represent the anti-scattering transmission and anomalous shunt phenomena of the edge state of valley topology respectively

  The team further revealed the anomalous shunt phenomenon of the edge state, that is, the shunt is related to the Angle between the interfaces of different topological phases. This anomalous shunt, which had been expected but not experimentally verified in graphene, has now been experimentally confirmed in on-chip valley topological materials (FIG. C).

  The realization of on-chip valley topological materials is expected to lead to the application of topological physics in micro-nano electromechanical systems and surface wave devices.

  The team has previously published articles in Nature Physics and Physics Review Letters with south China University of Technology as its first unit. Among them, Li Feng and Huang Xueqin were introduced by Outstanding Talents and Team Introduction Program of South China University of Technology, and Lu Jiuyang and Deng Weiyin were supported by Postdoctoral Innovative Talents Program. This paper is supported by the National Natural Science Foundation of China and the Pearl River Talent Program of Guangdong Province.