基于量子阱-金属-量子点结构的等离激元增强非辐射共振能量转移机制研究

In order to solve the limitation problem of coupling distance in the traditional non-radiative resonant energy transfer (NRET) process, this project propose new hybrid structures of quantum wells-metal-quantum dots (QWs-Metal-QDs). The designed hybrid structures can take advantage of metal-induced surface plasmon coupling to enhance the NRET process between QWs and QDs, which may break the close-distance requirement of the NRET process. The research will focus on the fabrication of III-nitride QWs-Metal-II-VI QDs hybrid structures and the complicated exciton recombination dynamics in the hybrid structures. It will investigate the surface plasmon enhanced NRET process in two different coupling systems based on nitride QW planar structures and nanostructures, so as to build up the model of surface plasmon enhanced NRET and clarify its principles. Meanwhile, this project will also explore the fabrication of these two kinds of hybrid white light-emitting diodes (LEDs) and do researches on the improvements of the color-conversion efficiency and Droop effect in hybrid white LEDs utilizing surface plasmon enhanced NRET, which paves a way to achieving next-generation white LEDs with high efficiency.

本项目针对传统非辐射共振能量转移（NRET）的耦合间距受限问题，提出了一种量子阱-金属-量子点的新型混合结构，旨在利用金属诱导等离激元增强量子阱-量子点间的NRET过程，以突破传统NRET近距耦合的限制。项目将围绕III族氮化物量子阱-金属-II-VI族量子点混合结构的制备及其内部复杂的激子复合动力学过程，重点研究基于氮化物量子阱平面结构和纳米结构的两种不同NRET耦合体系中的等离激元增强效应，建立等离激元增强NRET的物理模型，阐明其内部机理。同时探索制备基于这两种耦合体系的混合白光LED器件，研究等离激元增强NRET机制对混合白光LED器件的色转换效率和Droop效应的改善情况，为实现新型高效白光LED器件提供新思路、新途径。

非辐射共振能量转移是一种近距耦合作用，可以实现能量的无损传递，近些年已经成为色转换LED芯片的重要技术途径。但这一物理机制的主要限制在于其耦合间距有限。本项目提出了利用金属局域等离激元增强这一共振能量转移作用的新思路。项目系统研究了多种纳米阵列结构的制备技术（激光干涉光刻、聚苯乙烯小球自组装和金属颗粒热退火技术），成功制备了量子阱-金属-量子点的混合结构。重点研究了共振能量转移机制对金属局域等离激元共振波长的依赖关系，并建立了金属局域等离激元增强共振能量转移的物理模型，相关性能达到国际领先水平。最后，本项目实现了微米孔量子阱-量子点的混合LED器件，实现了色转换效率的提升和器件Droop效应的抑制。本项目研究对金属局域等离激元增强非辐射共振能量转移这一新技术途径提供了重要的理论和器件参考。