中国激光, 2019, 46 (6): 0614026, 网络出版: 2019-06-14
离轴涡旋光束诱导空气等离子体产生太赫兹波 下载: 1182次
THz Wave Generation from Air Plasma Induced by Off-Axis Vortex Beam
太赫兹波技术 空气等离子体 涡旋光束 空间光调制器 飞秒激光 terahertz technology air plasma vortex beam spatial light modulator (SLM) femtosecond laser
摘要
使用涡旋光束代替高斯光束作为产生光源,研究了涡旋光束产生太赫兹波的过程。探究了具有不同拓扑荷数的涡旋光束在产生太赫兹波时的差异,相位奇点的位置对产生太赫兹波的影响,不同脉冲强度和激光波长下涡旋光束产生的太赫兹波能量、频谱和偏振的变化。结果表明,产生的太赫兹波强度会随涡旋光束拓扑荷数的变化而变化,并且与涡旋中心的位置密切相关。涡旋光束所产生的太赫兹波随脉冲强度和激光波长的变化趋势与高斯光束一致。高斯光束与涡旋光束产生的太赫兹波在频谱和偏振上的变化趋势一致。
Abstract
This study aims to investigate the process of terahertz wave generation using a vortex beam generated by spatial light modulator rather than a Gaussian beam as the light source. Herein, we explore the differences among vortex beams with different topological charge numbers when generating terahertz waves. We find that the generation of terahertz waves is affected by the phase singularity position. In addition, we investigate the changes of terahertz wave energy, spectrum, and polarization produced by vortex beams with different pulse intensities and laser wavelengths. The results demonstrate that the intensity of the terahertz wave changes with the topological charge number, which is also closely related to the position of the vortex center. Under the same vortex beam, the variation of the generated terahertz wave with pulse intensity and laser wavelength is consistent with that for a Gaussian beam. Specifically, the terahertz waves generated by a vortex beam and a Gaussian beam are consistent in terms of spectrum and polarization.
蒋广通, 张亮亮, 吴同, 张存林. 离轴涡旋光束诱导空气等离子体产生太赫兹波[J]. 中国激光, 2019, 46(6): 0614026. Guangtong Jiang, Liangliang Zhang, Tong Wu, Cunlin Zhang. THz Wave Generation from Air Plasma Induced by Off-Axis Vortex Beam[J]. Chinese Journal of Lasers, 2019, 46(6): 0614026.