Tailoring single-cycle electromagnetic pulses in the 2-9 THz frequency   range using DAST/SiO2 multilayer structures pumped at Ti:sapphire wavelength
  We present a numerical parametric study of single-cycle electromagnetic pulse generation in a DAST/SiO2 multilayer structure via collinear optical rectification of 800 nm femtosecond laser pulses. It is shown that modifications of the thicknesses of the DAST and SiO2 layers allow tuning of the average frequency of the generated THz pulses in the frequency range from 3 to 6 THz. The laser-to-THz energy conversion efficiency in the proposed structures is compared with that in a bulk DAST crystal and a quasi-phase-matching periodically poled DAST crystal and shows significant enhancement. 
Andrei G. Stepanov, Andrii Rogov, Luigi Bonacina, Jean-Pierre Wolf,   Christoph P. Hauri
physics.optics