金-硫化镉核壳异质结构纳米材料的制备及表面等离激元-激子相互作用研究

The interaction of metal surface plasmon and semiconductor quantum dots is one of the current hottest issues in physics, and it has an important significance on the development of plasmonics and quantum information. In this project, we will investigate the synthesis of Au-CdS core-shell hetero-nanorods and their optical properties. By measuring the absorption spectra, emission spectra and fluorescence lifetime spectra of the Au-CdS core-shell hetero-nanomaterials, the influence of the shape, size and coupling distance on the optical properties will be clarified. The local electric field distribution and absorption spectra of the Au-CdS core-shell hetero-nanomaterials will be calculated by using the finite-difference time-domain (FDTD) method and discrete dipole approximation (DDA) method, respectively. On the basis of the experimental measurements and theoretical calculations, the variations of the optical properties induced by the interaction of the metal surface plasmon and semiconductor quantum dots will be explained. Through this project, a new metal-semiconductor nanostructure which aims at the supply for the research of light-matter interaction and for the potential applications will be provided. We have carried out a preliminary exploration of the method for hetero-nanomaterials synthesis and the optical properties measurement, which has laid a foundation for this project.

金属表面等离子体与半导体量子点的相互作用是当前物理学的研究热点之一，对表面等离激元光子学以及量子信息等领域的发展有着重要的意义。本项目以Au-CdS核壳异质结构纳米棒为主要研究对象，测量材料的吸收光谱、发射光谱、荧光寿命谱等，研究材料的形貌、尺寸、耦合距离等局域结构对其光学性质的影响。在此基础上，结合有限时域差分方法模拟局域电场以及离散偶极近似方法计算等离激元共振吸收峰，解释金属表面等离激元和激子耦合相互作用引起的材料光学性质的改变。本项目的研究工作旨在为光与物质相互作用研究以及潜在应用提供一种具有优良光学性质的金属-半导体纳米结构。我们已经进行了初步的探索，在金属和半导体纳米结构材料的合成、光学性质测试等方面积累了丰富的经验，为本项目的开展打下了基础。

本项目围绕Au-CdS核壳异质结构纳米材料的制备、光学性质测试以及相关应用开展研究工作。金纳米颗粒的合成是Au-CdS核壳异质结构纳米材料合成的基础。我们研究了在液相种子体系以及无种子体系金纳米棒的可控合成，并测试其光学性质。我们实现了基于纳米金饱和吸收体的大能量全固态激光器的激光运转。我们实现了立方体和棒状金核的Au-CdS核壳异质结构纳米材料的可控合成及其光学性质研究，并将其应用于罗丹明B的光催化降解。此外，我们还研究了其它纳米材料的光学性质，为后续研究工作的开展奠定了基础。