Terahertz magnetotransport in 2D electron systems: near-field effects, helicity, and non-locality

二维电子系统（2DES）的光响应是现代光电子学的核心。在这种情况下，近场光-物质相互作用的理解是凝聚态物理学和纳米光子学之间的边界的基本挑战。该项目的目标是为最近发现的2DES中的太赫兹（THz）磁输运现象的家族开发一个全面的理论，其中辐射的螺旋度，传输的非局部性和近场效应起着重要作用。具体而言，计划中的研究包括系统研究石墨烯、拓扑狄拉克材料和具有抛物线光谱的高迁移率2DES中的非局域伯恩斯坦等离子体模式介导的巨大近场太赫兹光响应，回旋共振吸收的有趣螺旋免疫性，以及亚太赫兹线性动态响应中螺旋敏感量子振荡的理论研究，最近在高精度透射率实验中已变得可检测到。计划的理论研究，沿着正在进行的相关实验在里根斯堡，维也纳，和新加坡，将提供一个即时验证所获得的理论结果，应导致更深入地了解基本的光电和传输特性的2DES和产生一个重要的反馈给研究界可能导致其技术设计和功能的重要进展。

The photoresponse of 2D electron systems (2DES) is at the heart of modern optoelectronics. In this context, understanding of the near-field light-matter interaction is a fundamental challenge at the boundary between condensed matter physics and nanophotonics. The goal of this project is to develop a comprehensive theory for a family of recently discovered terahertz (THz) magnetotransport phenomena in 2DES where the helicity of radiation, nonlocality of transport, and near-field effects play a major role. Specifically, the planned research includes systematic studies of the giant near-field THz photoresponse mediated by nonlocal Bernstein plasmon modes in graphene, topological Dirac materials, and high-mobility 2DES with parabolic spectrum, the intriguing helicity immunity of the cyclotron resonance absorption, and theoretical studies of helicity-sensitive quantum oscillations in the sub-THz linear dynamic response, which have recently become detectable in high-precision transmittance experiments. The planned theoretical studies, along with the ongoing related experiments in Regensburg, Wien, and Singapore that will provide an immediate verification of the obtained theoretical results, should lead to a deeper understanding of fundamental optoelectronic and transport properties of 2DES and yield an important feedback to the research community potentially leading to important advances in their technological design and functionalities.