Optically functional hybrid quantum dots

研究了半导体量子点中Au纳米粒子诱导的等离子体激元效应，旨在实现量子点中载流子与光的有效耦合。利用基于蛋白质工程的修饰分子链或纳米光刻技术，人工制备了各种具有光学功能的Au纳米粒子杂化量子点，其中量子点和Au纳米粒子之间的距离被有意地控制。在Si量子点中，观察到源于局域等离子体效应的光致发光（PL）强度的增强。然而，在具有高内量子效率的II-VI或III-V量子点中，由于量子点中激发态的能量转移到Au纳米颗粒中，而不是等离子体增强效应，PL强度显著降低。

Plasmonic effects induced by Au nano-particles in semiconductor quantum dots (QDs) were studied, aiming at efficient coupling between carriers in the QDs and lights. Various optically functional hybrid QDs with Au nano-particles were artificially fabricated, where the distance between the QD and the Au nano-particle was intentionally controlled by using modified molecular chains or nano-lithography techniques based on the protein engineering. In Si QDs, enhancements of the photoluminescence (PL) intensity originating from the localized plasmonic effect were observed. However, in II-VI or III-V QDs with high internal quantum efficiencies, PL intensities significantly decrease because of the energy transfer from the excited states in the QDs into the Au nano-particles, rather than the plasmonic enhancement effect.