金属纳米颗粒-薄膜间隙腔与单层过渡金属硫化物中面外激子的强耦合作用

实现光学谐振腔与单个量子发射体之间的的强耦合作用是应用腔量子动力学方法来研究和检验量子力学基本概念的重要内容，也是实现一系列尖端技术应用的基础条件。当前的研究集中于用金属纳米结构实现的超小光学谐振腔来增强光与分子、量子点等量子发射体之间的耦合强度，但是金属纳米腔模场与量子发射体之间的空间取向匹配一直是一个挑战。本项目提出利用具有面外激子响应的单层半导体材料MoTe2作为量子发射体，将其嵌入到金属纳米球-薄膜间隙腔中构成金纳米球-MoTe2-薄膜的层式耦合结构。由于面外激子跃迁偶极矩与间隙腔模场空间取向一致，因而自动满足优化的耦合匹配条件，产生最大的耦合强度。围绕这一核心内容，本项目将展开对金属纳米球-薄膜的模式调控和单层MoTe2的面外激子响应特性的深入研究，并探索金纳米球-MoTe2-薄膜结构产生室温强耦合作用的条件，为构建可靠实用的强耦合系统提供理论与实验基础。

Achieving strong coupling between optical resonator and quantum emitters is the key aspect of studying and testing of the fundamental concepts of quantum mechanics in the area of cavity-quantum electrodynamics(QEDs), which also benefits the development of cutting-edge applications such as fine-tuning of chemical reactions, ultralow-power threshold lasers and frequency conversion at the singe photon level. To strengthen the light-mater coupling, the current approaches rely on ultrasmall mode volume provided by metal nanostructures. However, the optimized alignment of the transition dipole moment of single emitters with respect to the cavity field remains a challenge. In this project we propose the out-of-plane excitons in monolayered semiconductors MoTe2 could be a good candidate of emitters with transition dipoles naturally aligned along the local fields in metal nanosphere-film cavity. Such an optimized alignment configuration for the emitter-cavity construct would result in strong coupling at room temperature and thus pave the way for fabrication of reliable and robust strong-coupling systems for practical applications.