Zhang Baolong, Wu Xiaojun, Wang Xuan, Li Shangqing, Ma Jinglong, Liao Guoqian, Li Yutong, Zhang Jie
Opt Lett. 2022 Jun 1;47(11):2678-2681. doi: 10.1364/OL.456498.
Controlling the time-domain oscillation of a terahertz (THz) wave offers promising capabilities for THz-based all-optical particle acceleration and strong-field THz nonlinear physics. However, the lack of highly efficient and frequency-modulable multicycle THz sources is impeding the spread of strong-field THz science and applications. Here, we show that by simply adding an echelon into a single-cycle THz source based on optical rectification in lithium niobate crystals via the tilted pulse-front technique, multicycle THz pulses can be efficiently generated with an 800 nm-to-THz efficiency of 0.1% at room temperature. The radiated THz properties can be engineered by precisely designing the echelon structure. Our proposed multicycle THz generation method has the advantages of high efficiency, ease of operation, and quick switching between single-cycle and multicycle working modes, all of which are important in the application of high-field THz radiation.
控制太赫兹（THz）波的时域振荡为基于太赫兹的全光粒子加速和强场太赫兹非线性物理提供了广阔的应用前景。然而，缺乏高效且频率可调的多周期太赫兹源阻碍了强场太赫兹科学及应用的推广。在此，我们表明，通过在基于倾斜脉冲前沿技术的铌酸锂晶体光整流单周期太赫兹源中简单地添加一个阶梯光栅，在室温下可以高效地产生多周期太赫兹脉冲，800纳米到太赫兹的转换效率为0.1%。通过精确设计阶梯光栅结构，可以调控辐射太赫兹波的特性。我们提出的多周期太赫兹产生方法具有效率高、操作简便以及在单周期和多周期工作模式之间快速切换的优点，所有这些在高场太赫兹辐射应用中都很重要。
