Аннотация:We report an extremely widely tuneable monochromatic Cherenkov phase-matched terahertz (THz) wave generator using a bulk lithium niobate crystal. This was achieved by optimizing the incident conditions of the pump beams, and the surface-emitting condition was produced by total internal reflection of the pump beam at the THz wave output surface of the nonlinear optical crystal. Effective generation at higher frequencies was realized by reducing the absorption inside the crystal, and as a result, we achieved a tuning range from 0.2 to 6.5 THz with a very simple configuration.
