报告题目： Some recent results of 3D topological materials (三维拓扑材料一些最新研究成果)
报 告 人：张超 教授 (School of Physics, University of Wollongong, NSW, Australia)
报告时间：2018年9月21日（周五）14:00
报告地点：校本部G309
报告摘要：
We discuss some thermionic, optical and transport properties of three dimensional Dirac materials. (1) In 3D Dirac materials, the energy equipartition theorem gives rise to an average energy of kBT. This is twice of the energy in traditional materials. This enhanced energy leads to an enhanced thermionic cooling efficiency which is higher than that in normal metal and in graphene. (2) Fast charge dynamics has been studied, taking into account the electron-acountic phonton and electron-optical phonon interaction. Results indicate that the charge relaxation is directly proportional to the gap. (3) Electronic structure of a Weyl semimetal and superconducting Weyl semimetal has been calculated. A dual gap structure has been revealed. The Andreev reflection can be used to directly map out the the dual gap characteristics.
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