Efficient generation of Cherenkov-type terahertz radiation from a lithium niobate crystal with a silicon prism output coupler

摘要

We report on the generation of broadband terahertz (THz) pulses using Cherenkov-type generation in magnesium oxide-doped lithium niobate (MgO:LN). The efficiency of the output coupling process of THz radiation at higher frequencies into free space is considerably increased by the use of a properly cut silicon prism. The achieved spectrum is broader compared to the normal Cherenkov-cut geometry. Due to a considerably reduced propagation length in the absorbing MgO:LN, the effective application of longer crystals is possible. Thus, the measured spectral intensity is much higher and the spectrum broader.