Weyl and Dirac semimetals and beyond– prediction, synthesis and characterization of new semimetals

韦尔和狄拉克半金属及其他新半金属的预测、合成和表征

• 批准号: 405940956
• 负责人: Dr. Saicharan Aswartham, Ph.D.
• 金额: --
• 依托单位: Institut für Festkörperforschung
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/405940956?language=en
• 关键词: Weyl; Dirac; semimetals; beyond; prediction

Presently, one of the most rapidly developing field in condensed matter is the physics of Dirac (DSM) and Weyl (WSM) semimetals, 3D graphene analogs that have not only a theoretical importance, but have a significant potential for practical applications as components of nanoelectronic devices, quantum computers, ultra-high-speed circuits, which answers actual challenges of the formation of digital economy. Obviously, all the consequences of the nontrivial topology of the electronic structure have not yet been fully investigated. One of the main reason is a lack of single crystals of these semimetals. Equally obvious is the fact that, in order to achieve a progress in studying of these materials, a close collaboration between theoretical and experimental physicists and solid state chemists is needed. Indeed, most of the DSM and WSM were first predicted by theory, then grown as single crystals and investigated by a number of techniques confirming non-trivial topological states.The goals of this project are theoretical prediction, synthesis as single crystals, and comprehensive studies of topological semimetals and derivative systems. The project will be conducted by the international teams from Moscow and Dresden which includes theoretical and experimental physicists (Leibnitz IFW, Dresden), as well as solid state and materials chemists, experts in inorganic synthesis (Department of Chemistry, Lomonosov Moscow State University). With this complementary expertise the important questions of the chemistry and physics of the topological semimetals will be addressed. As the first step new Weyl and Dirac semimetals will be synthesized and investigated. As the next step Dirac semimetals with multiple degenerate points of the electron band structure, which were predicted recently, will be synthesized and investigated. At present, semimetals of this type remain practically unexplored experimentally. Another question to be addressed in the present project is the change of the physical properties with doping and consequently change of the position of the Weyl and Dirac points with respect to the Fermi level.

目前，凝聚态中发展最快的领域之一是狄拉克（DSM）和外尔（WSM）半金属物理学，3D石墨烯类似物不仅具有理论重要性，而且作为纳米电子器件，量子计算机，超高速电路的组件具有重要的实际应用潜力，这回答了数字经济形成的实际挑战。显然，电子结构的非平凡拓扑的所有结果还没有被充分研究。主要原因之一是缺乏这些半金属的单晶。同样明显的是，为了在研究这些材料方面取得进展，需要理论和实验物理学家以及固态化学家之间的密切合作。事实上，大多数DSM和WSM首先通过理论预测，然后生长为单晶，并通过许多技术进行研究，确认非平凡的拓扑状态。本项目的目标是理论预测，单晶合成，以及拓扑半金属和衍生物系统的综合研究。该项目将由来自莫斯科和德累斯顿的国际团队进行，其中包括理论和实验物理学家（Leibnitz IFW，德累斯顿），以及固态和材料化学家，无机合成专家（莫斯科州立大学化学系）。有了这种互补的专业知识，拓扑半金属的化学和物理的重要问题将得到解决。作为第一步，新的Weyl和Dirac半金属将被合成和研究。作为下一步的狄拉克半金属与多个简并点的电子能带结构，这是最近预测，将合成和研究。目前，这种类型的半金属实际上还没有经过实验研究。在本项目中要解决的另一个问题是掺杂的物理性质的变化，从而改变的位置的外尔和狄拉克点相对于费米能级。