Output Enhancement of a THz Wave Based on a Surface-Emitted THz-Wave Parametric Oscillator

High-power nanosecond pulsed THz-wave radiation is achieved via a surface-emitted THz-wave parametric oscillator. One MgO:LiNbO₃ crystal with large volume is used as the gain medium. THz−wave radiation from 1.084 THz to 2.654 THz is obtained. The maximum THz-wave average power is 5.8 µW at 1.93 THz when the pump energy is 84 mJ, corresponding to a energy conversion efficiency of 6.9×10⁻⁶. The polarization characteristics of THz wave are analyzed. During the experiments the radiations of the first-order and the second-order Stokes wave are observed.