论文标题
Terahertz场在飞秒激光器中引起了接近切割的均匀谐波
Terahertz field induced near-cutoff even-order harmonics in femtosecond laser
论文作者
论文摘要
在强度强的Terahertz（THZ）场的存在下，飞秒激光脉冲的高阶谐波生成在强场近似下进行了研究，显示出与THZ电场的近定位均匀均匀谐波（NCEH）幅度的简单比例。对于连续波和高斯脉冲，分析显示了THZ诱导的NCEHS的形成。关于THZ场与飞秒脉冲的频率比的扰动分析表明，THZ诱导的NCEHS源自其一阶校正，并且该现象的可用参数条件也被阐明。由于宽带THZ场的时间域波形的完整表征对于多种应用至关重要，因此该作品提供了一种替代的时间分辨现场检测技术，从而允许在THZ光谱范围内对脉冲的强大宽带表征。
High-order harmonic generation by femtosecond laser pulse in the presence of a moderately strong terahertz (THz) field is studied under the strong field approximation, showing a simple proportionality of near-cutoff even-order harmonic (NCEH) amplitude to the THz electric field. The formation of the THz induced-NCEHs is analytically shown for both continuous wave and Gaussian pulse. The perturbation analysis with regard to the frequency ratio of the THz field to the femtosecond pulse shows the THz-induced NCEHs originates from its first-order correction, and the available parametric conditions for the phenomenon is also clarified. As the complete characterization of the time-domain waveform of broadband THz field is essential for a wide variety of applications, the work provides an alternative time-resolved field-detection technique, allowing for a robust broadband characterization of pulses in THz spectral range.
