The THz regime is widely appealing across many disciplines including solid-state physics, life sciences, and increasingly in particle acceleration. Multicycle THz pulses are typically formed via optical rectification in periodically poled crystals. However the manufacturing procedures of these crystals limit their apertures to below ~1 cm, which from damage limitations of the crystal, limits the total pump power which can be employed, and ultimately, the total THz power which can be produced. Here we report on the simple in-house fabrication of a periodically poled crystal using ~300 μm thick wafers. Each wafer is consecutively rotated by 180^∘ to support quasi-phase matching. We validate the concept with a Joule-class laser system operating at 10 Hz and measure up to 1.3 mJ of energy at 160 GHz, corresponding to an average peak power of approximately 35 MW and a conversion efficiency of 0.14%. In addition, a redshifting of the pump spectrum of ~50 nm is measured. Our results indicate that high-power THz radiation can be produced with existing and future high-power lasers in a scalable way, setting a course toward multi-gigawatt multicycle THz pulses.

太赫兹谱系在包括固体物理学，生命科学以及越来越多的粒子加速在内的许多学科中具有广泛吸引力。通常通过光学整流在周期性极化的晶体中形成多周期THz脉冲。但是，这些晶体的制造程序将其孔径限制在〜1 cm以下，这受晶体损坏的限制，限制了可以使用的总泵浦功率，并最终限制了可以产生的总THz功率。在这里，我们报告了使用〜300μm厚晶圆的简单内部制造周期性极化晶体的方法。每个晶片连续旋转^180∘支持准相位匹配。我们使用10 Hz的焦耳级激光系统验证了该概念，并在160 GHz时测量了高达1.3 mJ的能量，相当于约35 MW的平均峰值功率和0.14％的转换效率。另外，测得泵浦光谱的红移为〜50 nm。我们的结果表明，现有和未来的大功率激光器可以以可扩展的方式产生大功率太赫兹辐射，为多吉瓦多周期太赫兹脉冲的发展奠定了基础。