摘要
基于渡越-切伦科夫辐射原理,单色飞秒激光脉冲聚焦到空气中形成等离子体进而辐射出径向偏振太赫兹波,径向偏振太赫兹波经过紧聚焦后在焦点处产生太赫兹波横向偏振分量。为了有效调控太赫兹横向分量的频率分布和振幅特性,首先,通过理论分析太赫兹横向场分量在外加电压下的分布规律,给出不同角度的外加电压对太赫兹横向场频率强度的影响。然后,采用对等离子体施加外部电场的方法,得到一个最佳的纵向电场角度产生高强度太赫兹横向偏振分量。对发展太赫兹波特性的基础研究以及太赫兹技术的应用具有重要的参考意义。
Based on the principle of transit-Cherenkov radiation, transverse polarized components of terahertz waves will be generated at the focal point after compact focusing when the single-color femtosecond laser pulses were focused into the air to form plasma and then radiate radially polarized terahertz waves. In order to effectively control the frequency distribution and amplitude characteristics of terahertz transverse field components, firstly, the distribution of terahertz transverse field components under the external electric field is theoretically analyzed, and the influence of the external electric field at different angles on the frequency intensity of terahertz transverse field is given. Then, through experimental verification, a better longitudinal electric field angle is obtained to produce stronger THz transverse polarization component. This work provides an important reference for the basic research of THz wave characteristics and the application of THz technology.
作者
周市委
李恬
王莹莹
严俊
彭滟
朱亦鸣
ZHOU Shiwei;LI Tian;WANG Yingying;YAN Jun;PENG Yan;ZHU Yiming(Shanghai Key Laboratory of Modem Optical System,University of Shanghai for Science and Technology,Shanghai 200093,China)
出处
《光学仪器》
2020年第1期63-67,共5页
Optical Instruments
基金
国家自然科学基金(61722111,61771314)
上海市启明星计划(17QA1402500)。
关键词
太赫兹波
横向偏振
外部电场
terahertz
transverse polarized
external electric field
