关联单个Ag纳米粒子的第二波光学反应与形态
Rongchao Jin1, Justin E Jureller, Hee Y Kim
1Department of Chemistry, James Franck Institute, and Consortium for Nanoscience Research, University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, USA.
Journal of the American Chemical Society
|September 8, 2005
概括
单个银纳米粒子表现出第二波 (SH) 生成,非线性光学效应. SH活动与纳米粒子的形状和结构相关,这表明一个共振振荡器机制.
科学领域:
- 纳米光子学 纳米光子学
- 非线性光学是非线性光学.
- 材料科学 材料科学 材料科学
背景情况:
- 二次波 (SH) 生成是一个关键的非线性光学现象.
- 了解单个纳米粒子中的SH活性对于纳米级光学应用至关重要.
- 描述纳米粒子形态和光学反应是具有挑战性的.
研究的目的:
- 为了研究单个银纳米颗粒的SH活性.
- 为了将SH生成与精确的纳米粒子形态相关联.
- 阐明纳米结构中SH活性的潜在机制.
主要方法:
- 用五秒激光激发来测量SH活动.
- 使用带有位置标记的传输电子显微镜 (TEM) 用于高分辨率成像.
- SH测量与粒子形态 (纳米球,纳米棒,集群) 相相关.
主要成果:
- 单个纳米粒子结构和SH活性之间确立了直接的相关性.
- SH活动显示出明显的光谱和功率依赖.
- 在纳米球,纳米棒和集群结构之间观察到SH反应的差异.
结论:
- 这些发现强烈表明,用于SH生成的一光子共振驱动的非线性振荡器机制.
- 这项研究提供了纳米尺度结构和非线性光学特性之间的直接联系.
- 该方法使光学特性与单个纳米结构的形态学能够精确相关.
相关概念视频
Molecular Spectroscopy: Absorption and Emission
Molecules possess discrete energy levels called quantum states. Unlike atoms, which have simpler energy levels, molecules possess additional rotational and vibrational energy levels. Each energy level is separated by an energy gap, with the gaps between adjacent electronic, vibrational, and rotational levels varying significantly. The three types of energy levels in a diatomic molecule are shown in Figure 1.
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