Radiataive and Ultrafast Non-radiative Electronic Relaxation in Individual and Assembled Noble Metallic Nanopartiacles of Different Shapes

不同形状的单个和组装贵金属纳米粒子的辐射和超快非辐射电子弛豫

• 批准号: 0527297
• 负责人: Mostafa El-Sayed
• 金额: --
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-15 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0527297&HistoricalAwards=false
• 关键词: Radiataive; Ultrafast; Non; radiative; Electronic

This project focuses on the nanometer size scale where material properties differ from bulk properties and change as their size or shape changes. It addresses nonradiative properties of individual gold and silver nanoparticles and the effects of interparticle coupling on these properties. A new capability in electron beam lithography capable of producing nanoparticles as small as few nanometers will be used to focus on changes in relaxation processes and the period of the coherent lattice oscillations (produced by femtosecond electronic laser excitations) as the size, shape and the interparticle distances change. The effect of the substrate on interparticle coupling will also be examined. The changes in these properties will give an understanding of the nature of the coupling of these assembled particles.The broader impacts of this project are both educational and industrial in nature. For example, with regard to the properties of individual Noble metal nano-particles, as their size and shape changes their ability to scatter and absorp light strongly changes, and these properties can be used to record clear images of single cancer cells. Another property of these nanoparticles is that strongly absorbed light energy is rapidly converted into heat, a property that can be used to selectively destroy cancer cells by using a very low level of laser radiation that is not harmful to healthy cells. Thus understanding properties of individual nanoparticles enables novel applications, and students trained in these areas are very competitive in the academic, industrial and National Laboratory job markets related to broad fields of nanotechnology.

该项目的重点是纳米尺寸尺度，其中材料性质不同于体积性质，并随着其尺寸或形状的变化而变化。 它解决了单个金和银纳米粒子的非辐射特性和粒子间耦合对这些特性的影响。一种新的能力，在电子束光刻能够生产纳米粒子小到几个纳米将被用来集中在弛豫过程中的变化和相干晶格振荡（由飞秒电子激光激发产生）的大小，形状和粒子间的距离变化的周期。 还将检查衬底对粒子间耦合的影响。 这些性质的变化将使人们了解这些组装粒子的耦合性质。这个项目的更广泛的影响是教育和工业的性质。例如，关于单个贵金属纳米颗粒的性质，随着它们的尺寸和形状的变化，它们散射和吸收光的能力强烈变化，并且这些性质可以用于记录单个癌细胞的清晰图像。这些纳米颗粒的另一个特性是，强烈吸收的光能迅速转化为热量，这种特性可以通过使用对健康细胞无害的非常低水平的激光辐射来选择性地破坏癌细胞。因此，了解单个纳米粒子的特性可以实现新的应用，在这些领域接受培训的学生在与纳米技术广泛领域相关的学术，工业和国家实验室就业市场上非常有竞争力。