基于表面等离子体激元共振的飞秒抽运探测技术研究

对基于表面等离子体激元共振（SPR）的飞秒抽运探测技术进行了系统地数字分析.计算结果表明，利用SPR技术可将飞秒抽运探测信号强度ΔR/R提高2—3个数量级，其提高的比例依赖于金属膜的厚度和探测光的入射角，其中R和ΔR分别为探测光反射率的总量和变化量.特别地，对于金属-吸收介质体系，金属膜的介电常数变化对ΔR的影响仅为吸收介质影响的2%，所以ΔR/R主要反应吸收介质中的动力学过程，因此该技术对研究表面和界面的超 关键词： 超快光学 表面等离子体共振 飞秒抽运探测技术 信号强度

Femtosecond pump-probe technique assisted by surface plasmon resonance

Femtosecond pump-probe technique assisted by surface plasmon resonance (SPR) is investigated numerically in this paper. Our calculations show that the signal ratio AR/R is increased by 2--3 orders of magnitude higher than the standard pump-probe technique, where AR and R are the intensity change and total intensity of the probe beam, respectively. It should also be pointed out that AR/R is sensitive to the incident angle of the pump beam and the thickness of the metal film. In particular for the metal-absorbing material system, AR induced by the hot electrons in the metal is only 2 percent of that induced by excited absorbing material, so AR/R is mainly related to the dynamics of the absorbing material. This technique will be interesting in investigating the uhrafast surface dynamics of thin films.