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Narrowband THz generation via chirp-and-delay in PPLN

High-peak-field, narrowband terahertz (THz) sources are well suited for compact electron acceleration [1], however, these sources are still under development and yet to reach optimal energies. A high conversion efficiency via difference frequency generation is established by quasi-phase matching in periodically poled lithium niobáte (PPLN). Moreover, to achieve the required mJ-level THz pulses high energy input pulses are inevitable [2]. Chirp-and-delay pumping offers a method to increase the NIR pulse duration and to scale up the energy without damaging the crystal. Here, we present chirp-and-delay in PPLN of varying poling periods and study the effect of crystal length and temperature.