不闪的半导体纳米晶体
Xiaoyong Wang1, Xiaofan Ren, Keith Kahen
1Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.
Nature
|May 12, 2009
概括
研究人员开发了非闪的半导体纳米晶体. 这些CdZnSe/ZnSe纳米晶体显示连续光发光,克服了单光子源和生物标签等应用的主要限制.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 量子光学是一种量子光学.
背景情况:
- 来自分子和纳米晶体的光发光表现出"闪" 间歇性的开/关强度波动.
- 半导体纳米晶闪的理论是由于通过非辐射再组合的临时电荷诱导火.
- 尽管进行了广泛的研究,但实现非闪的纳米晶体和充分理解闪仍然是一个挑战.
研究的目的:
- 合成和特征半导体纳米晶体,显示连续的,非闪的光发光.
- 为了研究带电纳米晶体的光发光特性.
- 了解核心/外纳米晶体中非闪行为的结构基础.
主要方法:
- 三元核心/外CdZnSe/ZnSe半导体纳米晶体的合成.
- 在连续光激发下,光发光强度,光谱形状和寿命的表征.
- 纳米晶体封闭潜力的建模,以阐明结构性质.
主要成果:
- 个别的CdZnSe/ZnSe纳米晶体表现出连续的,不闪的光发光.
- 这些纳米晶体表现出强烈的光发光,尽管充电,由多峰光谱和短寿命证明.
- 结构分析表明一个辐射分级合金组成,而不是一个利的核心/外接口.
结论:
- 开发的CdZnSe/ZnSe纳米晶体克服了半导体纳米晶体闪的局限性.
- 带电纳米晶体的连续光发光挑战了关于闪机制的先前假设.
- 这些不闪的纳米晶体对于需要稳定的单光子发射的应用具有重大潜力.
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