摘要
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。
By placing a pair of linear electrodes at the focal point of a femtosecond laser,the plasma generated through the laser-ionized air is placed in the bias direct-current(DC)field generated by the linear electrode.We observe the terahertz characteristics of plasma in the bias-electric field in this case.By scanning the linear electrodes and observing the terahertz wave intensity,we obtain the optimal electrode position for enhancing the amplitude of terahertz wave.Results suggest that as the laser power increases,the optimal position moves in the direction of light propagation.This work not only studies the characteristics of terahertz signal generated through plasma under the modulation of linear electrodes,but also reveals the physical characteristics of plasma.
作者
冯世嘉
董立泉
马丹妮
吴同
张亮亮
赵跃进
Feng Shijia;Dong Liquan;Ma Danni;Wu Tong;Zhang Liangliang;Zhao Yuejin(Beijing Key Laboratory for Precision Optoelectronic Measurement Instrument and Technology,School of Optics and Photonics,Beijing Institute of Technology,Beijing 100081,China;Key Laboratory of Terahertz Optoelectronics,Ministry of Education,Beijing Key Laboratory for Terahertz Spectroscopy and Imaging,Beijing Advanced Innovation Center for Imaging Technology,Department of Physics,Capital Normal University,Beijing 100048,China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2020年第10期169-173,共5页
Acta Optica Sinica
基金
国家自然科学基金(61935001)
北京市自然科学基金(JQ18015)。
关键词
光谱学
太赫兹波
等离子体
线状电极
偏置电场
spectroscopy
terahertz wave
plasma
linear electrodes
bias-electric field
