This invention discloses a continuous terahertz wave
radiation source based on optical
parametric oscillation in a
waveguide cavity, its usage method, and its fabrication method, belonging to the field of
optical communication technology. The continuous terahertz
parametric oscillation radiation source includes a nonlinear
dielectric waveguide layer and a substrate
waveguide layer disposed on the upper and lower surfaces of the nonlinear
dielectric waveguide layer. Reflective films are disposed on two opposite sides of the nonlinear
dielectric waveguide layer to form a waveguide cavity within the nonlinear dielectric waveguide layer. The thickness and width of the nonlinear dielectric waveguide layer both satisfy the
wave vector matching condition, and the thickness of the nonlinear dielectric waveguide layer is 5~50 μm. By obtaining a large
nonlinear coupling coefficient, a small terahertz propagation loss, and achieving
wave vector matching, the continuous terahertz wave
radiation source provided by this invention can achieve high terahertz conversion efficiency, the waveguide cavity has a high quality factor, enhances the effective
field strength within the nonlinear dielectric waveguide layer, and significantly reduces the terahertz
parametric oscillation threshold.