Numerical Investigations of THz-Wave Generation in Photonic Crystal Waveguide

We have presented a numerical analysis to describe the behavior of a quasi-monochromatic pulsed terahertz (THz) wave generation in photonic crystal waveguide (PCW) reported in our group. The frequency-dependent characteristic of the THz-wave generation is investigated numerically by the finite-difference time-domain method. Two different types of phase matching condition are achieved in the basics of the guided mode or air band in the PCW. The calculated THz output spectrum agrees well with the previous experiment one. This letter provides an effective estimation of THz-wave output characteristics and could be used to design the efficient coherent THz-wave source.