Enhancement and modulation of terahertz radiation by multi-color laser pulses

• 来源期刊: 中国物理B（英文版）
• 关键词: THz generation multi-color scheme laser-plasma interaction uncommon frequency ratio
• 年，卷（期）: 2018,（8）
• 页码范围: 285-289
• 页数: 5页
• 语种: 英文
• DOI: 10.1088/1674-1056/27/8/084209

摘要

We study theoretically intense terahertz radiation from multi-color laser pulse with uncommon frequency ratios. Com-paring the two-color laser scheme, of which the uncommon frequency ratio should be set to be a specific value, we show that by using multi-color harmonic laser pulses as the first pump component, the lasers as the second pump component can be adjusted in a continuous frequency range. Moreover, these multi-color laser pulses can effectively modulate and enhance the terahertz radiation, and the terahertz yield increases with the increase of the wavelength of the uncommon pump com-ponent and is stable to the laser relative phase. Finally, we utilize the electron densities and velocities of ionization events to illustrate the physical mechanism of the intense terahertz generation.