Q频移II-VI族CdSe/ZnS纳米晶体量子点准白光激射的若干关键问题研究

Laser behavior of monodispersed Q-shifted II-VI CdSe/ZnS nanocrystal qunatum dots (QDs) doped in gain media is studied based on the theory of level transiation emission of QDs by utilizing the quantum size effect, surface polarization effect and Q-shift property, and employing the muliti-granularity doping thchnique and the fiber lasing resonator. Mechanism of level translation emission of the QDs is investigated according to the revealed lasing phenomenon and lasing law. Therefore, a sub-white light laser characterized by low exciting threshold, continuous and steady working at room temperature can be implemented in laboratory for the first time.. As an original project presented in this apllication, its primary principle and technique are different from the MBE III-V QD laser and the conventional white-light laser. This project creates a novel type of sub-white light laser, developing broad applications in science, materials, biology and medicine, keeping ahead in the laser field in the world.

基于量子点受限能级的辐射跃迁理论，利用量子点的尺寸效应、表面极化效应和Q频移特性，采用多粒度掺杂和光纤光栅线性谐振腔技术，通过研究单分散的、Q频移II-VI族CdSe/ZnS纳米晶体量子点在增益介质中的光致激射行为的若干关键问题，揭示II-VI族纳米晶体量子点的激射现象，探索CdSe/ZnS量子点能级跃迁辐射机理，掌握多波长激射规律，在实验室首次实现低阈值、持续、稳定和可在室温下工作的准白光激射。.本项目为首创，其基本思想和技术路线不同于分子束外延自组织生长的III-V族量子点激光，与利用非线性效应将窄谱展宽的传统白光激光也完全不同。本项目开创了一种完全新型的准白光激光，为白光激光在科学、材料、生物医学等领域开辟了极为广阔的应用前景，形成我国在该领域的领先优势。

本项目在近年来发展迅速的半导体纳米晶体量子点研究的背景下展开。. 本项目基于量子点量子约束能级的辐射跃迁理论，利用量子点辐射波长的尺寸依赖、增益介质中的量子点表面极化效应特性，采用光纤光栅谐振腔技术，通过研究单分散纳米晶体量子点在增益介质中的光致激射行为，发现了量子点的激射现象和规律，揭示了量子点能级跃迁辐射机理，发现了量子点辐射跃迁截面的增宽机理和原因，确定了量子点能级的辐射跃迁截面，在实验室首次成功实现了低阈值、持续、稳定和在室温下工作的量子点激射。. 本项目开创了一种全新的、波长从红外到可见区可调的激射，形成了我国在该领域的领先优势，并为在科学、材料、生物医学等领域开辟了极为广阔的应用前景。