1 北京理工大学光电学院北京市精密光电测试仪器与技术重点实验室, 北京 100081
2 首都师范大学物理系太赫兹光电子学教育部重点实验室,太赫兹波谱与成像北京市重点实验室, 北京成像技术高精尖创新中心, 北京 100048
将线状电极置于飞秒激光聚焦点处,使激光电离空气产生的等离子体处于线状电极产生的偏置直流电场中,观察等离子体辐射太赫兹波的特性。通过扫描电极并观察太赫兹波强度,得到了增强太赫兹波幅值的最佳位置,并且发现随着激光功率的增大,最佳位置沿光传播方向移动。该研究不仅探讨了线状电极调制下等离子体产生太赫兹波的特征,还揭示了等离子体的物理特性。
光谱学 太赫兹波 等离子体 线状电极 偏置电场 光学学报
2020, 40(10): 1030001
Author Affiliations
Abstract
1 Beijing Key Laboratory for Precision Optoelectronic Measurement Instrument and Technology, School of Optics and Photonics, Beijing Institute of Technology, Beijing 100081, China
2 Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
3 Key Laboratory of Terahertz Optoelectronics, Ministry of Education, Beijing Key Laboratory for Terahertz Spectroscopy and Imaging, and Beijing Advanced Innovation Center for Imaging Technology, Department of Physics, Capital Normal University, Beijing 100048, China
To make further understanding of terahertz (THz) wave generation from liquid water, we study THz wave emission from water lines of different diameters. The water line with a smaller diameter generates a stronger THz electric field for the diameters from 0.2 mm to 0.5 mm. The THz electric field strength and polarity change with the relative position between the incident laser and water line. Moreover, the THz energy has an optimal radiation angle of about 60°. A two-dimensional dipole array model is introduced to illustrate the phenomenon. Our observations contribute to optimizing the scheme of the liquid THz source.
terahertz generation water lines Chinese Optics Letters
2020, 18(2): 023202
