界面扩散工程调控拓扑晶体绝缘体异质结巨线性磁电阻及其能带结构研究

拓扑量子材料开发与新奇物理现象调控是当前信息功能材料研究的主流与热点，是推动新一代信息产业革命的先导与基础。在此背景下，本项目聚焦在拓扑晶体绝缘体薄膜的拓扑表面态调控，相关巨线性磁电阻效应调控，及物理机制研究这一前沿科学问题，针对薄膜的体空穴抑制这一难点问题，独辟蹊径的采用界面扩散工程的新颖研究思路，精确调控薄膜的体载流子浓度与晶格对称性，实现其拓扑表面态及相关巨线性磁电阻调控这一目标。通过第一性原理计算与角分辨光电子能谱观测，结合量子输运理论，发现拓扑晶体绝缘体产生巨线性磁电阻效应背后的能带结构特征，建立此效应的物理机制模型及统一调控规律。通过本项目研究，可以解决拓扑晶体绝缘体的拓扑表面态与巨线性磁电阻之间物理关联这一科学问题，这将对推动拓扑电子学的前沿发展起到关键性引领性作用，也将为丰富拓扑材料的电输运理论进行成果开拓，并对量子器件的制备提供潜在的贡献。

The development of topological quantum materials and the regulation of novel physical phenomena are the mainstream and focus of the current information functional materials research. It is the front and foundation to promote the new information industry revolution. In this project, we focus on the research of topological surface state regulation from the topological crystal insulator films, related giant linear magnetoresistance effect regulation and its physical mechanism. For solving the problem of bulk hole density suppression, a new research idea of interface diffusion engineering is proposed to precisely control the bulk carrier concentration and lattice symmetry of thin films. The topological surface state and the related giant linear magnetoresistance regulation are realized. Through the first principle calculation and angle resolved photoelectron spectroscopy observation, combined with the quantum transport theory, we try to find the energy band structure characteristics of the topological crystalline insulator which induce giant linear magnetoresistance effect. We also try to establish the physical mechanism model and unified regulation law to explain this new type of magnetoresistance effect. Through the research of this project, we can solve the scientific problem of physical correlation between topological surface state of topological crystalline insulator and giant linear magnetoresistance, which will play a key leading role in promoting the frontier development of topological electronics, and will promote the electric transport theory of topological materials to achieve pioneering results, and then finally provide potential contribution to the preparation of quantum devices.