拓扑与关联体系的原位输运与扫描隧道电势测量研究

作为基础学科和现代诸多技术应用的科学基础，凝聚态物理提供对多粒子系统微观状态的理解。输运测量是探测凝聚态体系微观状态的主要手段之一。然而从常规输运测量所能得到的有限信息反演得出微观模型、微观机制的研究过程往往面临困难。本项目将利用过去几年中申请人团队着力发展的原位量子输运测量和扫描隧道电势测量两项领先的实验技术，在进行常规的变温、变磁场、变栅电压的测量之上，通过光子、离子、原子、分子束流与样品相互作用，实现对样品的连续、高精度、多参量调控和探测，从而在很大程度上扩大输运实验的参量空间，有力推动对输运现象内在机制的研究。我们计划选取低维量子材料作为研究对象，在拓扑相变的多场调控、反常霍尔效应的机理、关联体系的调控三个重要科学问题上开展研究，为理解这些效应的物理机制带来新的认识。

As the foundation of basic sciences and many modern technological applications, condensed matter physics serves to provide understanding to the microscopic states in many-body systems. Transport measurement, in this regard, is the main tool for the detection of the microscopic states in the condensed matter. However, conventional transport measurement can only obtain limited information from the subject of study, which poses difficulties in deducing the microscopic models and microscopic mechanisms from transport data. In this project, we plan to use two advanced experimental techniques we developed in recent years to tackle this issue. These techniques are called in-situ quantum transport measurement and in-situ scanning tunneling potentiometry. In addition to conventionally tunable parameters such as temperature, magnetic field and gate voltages, our new method also tunes the sample itself via interaction of the sample with fluxes of highly controlled photons, ions, atoms and molecules in ultra-high vacuum environment, thus realizing continuous, highly precise and multi-variable control and detection. In this way, we greatly enlarge the parameter space of a transport experiment, which substantially facilitate the research of the internal mechanism governing a specific transport phenomenon. We plan to study low-dimensional quantum materials, to bring new understanding to the mechanisms behind the following three important scientific problems: multi-field control of topological phase transition, mechanisms to cause anomalous Hall effect and tuning of the correlated electron systems.