Dates
General information
In the proposed project, the new schemes for high-power THz-wave generation (in both regimes of multi-cycles and nearly single-cycle THz pulses radiation) by optical rectification of femtosecond laser pulses will be developed and implemented. It is proposed to use a two-dimensional periodically poled lithium niobate structure (2-D PPLN) to satisfy the phase matching condition in mutually orthogonal directions of laser and THz wave propagation. The new method to realize large aperture two-dimensional PPLN structures will be developed. The artificial 2-D PPLN structures can be formed by placing the 1-D binary phase mask (with periodically repeating slits, along the y-axis) in front of a common 1-D PPLN, which already has a sign-modulated nonlinear coefficient d33 = d33(x) that varies along x-axis. The THz generation in artificial 2-D PPLN structures will be theoretical and experimental studied. According preliminary estimations, in 4 mm x 4 mm aperture 2-D structures the peak power of a nearly single-cycle and energy of multi-cycle THz pulses can reach 30 - 50 MW and 0.7 – 1.5 mJ, respectively. The developed source will be used to control advanced materials using a strong electric field of THz pulse.
