二维Bi2Se3光电功能器件的设计与应变调控

应变工程是调控与优化二维半导体器件性能的重要途径之一，其中压电极化调控可满足电子功能器件的力电光耦合和多功能化的应用需求。单层或少层的二维材料相比块体材料更易于实现压电极化和应变调控。二维材料压电极化的研究尚处于起步阶段，本项目拟基于高质量且厚度可控的二维Bi2Se3单晶，实现压电调制的多功能器件，研究Bi2Se3的电学、光学、力学性质与晶格各向异性、拓扑绝缘性质之间的关系，进而利用应变工程的压电极化效应对载流子传输进行调控，实现力电光耦合。同时，从理论和实验上探索Bi2Se3的压电极化调控拓扑绝缘体中狄拉克表面态变化，并结合二维Bi2Se3中压电极化和拓扑绝缘性两者的调控优势，为设计和构建高性能Bi2Se3晶体管、光电探测器，应变传感器和压电纳米发电机等多种功能集于一身的新型光电子器件提供理论依据与技术参考。

Strain engineering is one of the important approaches to regulate and optimize the performance of two-dimensional (2D) semiconductor devices, in which the piezoelectric polarization regulation can meet the needs of the force-electricity-light coupling and multifunction of electronic devices. 2D materials with single or few layers are easier to achieve the piezoelectric polarization and strain regulation than bulk materials. The research of the piezoelectric polarization of 2D materials is still in its infancy. Based on 2D Bi2Se3 single crystals of high quality and controllable thickness, this project is intended to realize piezoelectric regulated multifunctional devices. The relationship between the electrical, optical and mechanical properties and the lattice anisotropy, topological insulator properties of the Bi2Se3 can be studied. Then, the piezoelectric polarization effect of strain engineering can regulate the carrier transport and realize the force-electricity-light coupling. Meanwhile, the Dirac surface states of the topological insulator regulated by the piezoelectric polarization can be explored theoretically and experimentally. Combined the advantages of the piezoelectric polarization and the topological insulator, it is expected to provide scientific basis and technical reference for the design and fabrication of the novel optoelectronic devices including high performance Bi2Se3 transistors, photodetectors, strain sensors and piezoelectric nanogenerators etc.