Institute of Applied Physics Russian Academy of Sciences, 46 Ul’yanov Street, Nizhny Novgorod, 603950, Russia.
Opt Lett. 2012 Jul 1;37(13):2520-2. doi: 10.1364/OL.37.002520.
Results of experimental and theoretical investigations on generation of terahertz radiation at the interaction of femtosecond laser pulses with a metal surface are presented. Investigations are performed with the laser pulse intensities higher compared with that used in papers [Opt. Lett.29, 2674 (2004); Opt. Lett.30, 1402 (2005)]. The most effective generation is observed for p-polarized optical pulses with incidence angles in the range 5°-10° (from the surface), depending on the kind of metal. For the copper, the exponential growth of terahertz pulse energy with the increase of optical pulse energy was registered. Theoretical interpretation for some of the experimental results is proposed based on the model of free electrons in metal.
本文介绍了飞秒激光脉冲与金属表面相互作用产生太赫兹辐射的实验和理论研究结果。与文献[Opt. Lett.29, 2674 (2004); Opt. Lett.30, 1402 (2005)]中使用的激光脉冲强度相比，本研究中的激光脉冲强度更高。在实验中，观察到在一定范围内（取决于金属种类），当光学脉冲的入射角为 5°-10°（相对于表面）时，p 偏振光脉冲的产生效果最佳。对于铜，我们记录到太赫兹脉冲能量随光学脉冲能量的指数增长。基于金属中自由电子的模型，对部分实验结果提出了理论解释。
