It is theoretically shown that application of a phase mask in optical rectification scheme is equivalent to spatial modulation of the crystal’s nonlinear coefficient in cross-section plane of the laser beam. It allows using the technique of quasi-phase-matching for efficient noncollinear terahertz (THz) generation by using high-power wide-aperture optical beam. According to calculations, the linewidth of THz generation can be varied from 10 GHz to a few THz by changing the optical beam size. It is shown that the frequency of THz generation can be also tuned by building the image of the phase mask in the crystal with variable magnification.
© 2012 Optical Society of America
Original Manuscript: July 6, 2012
Manuscript Accepted: July 31, 2012
Published: September 28, 2012
Yuri Avetisyan and Masayoshi Tonouchi, "Terahertz generation in quasi-phase-matching structure formed by a phase mask," Opt. Lett. 37, 4155-4157 (2012)