Interferometric spectral-shaping for multicycle THz generation using the Chirp & Delay technique

Intense multicycle THz pulse generation has become possible using the chirp & delay technique with high-energy, broadband laser systems, but has so far been limited to few-Hertz repetition rates. Emerging applications are increasingly calling for extension to higher (kHz) repetition rates, but the traditional form of the technique is not well suited for use with available high-energy, high average-power laser systems due to the loss of temporal overlap between the two chirped pulses associated with their narrow optical bandwidths. Here we propose and demonstrate use of interferometric spectral shaping to overcome limitations in the conversion efficiency when generating THz frequencies limited by the optical bandwidth.