Green laser induced terahertz tuning range expanding in KTiOPO_4 terahertz parametric oscillator

摘要

532 nm green laser is utilized to achieve terahertz tuning range expanding in KTiOPO_4 terahertz parametric oscillator. With the theoretical analysis of the stimulated polariton scattering, an expanded tunability of the KTiOPO_4 terahertz parametric oscillator can be realized. A wide terahertz output tuning range from 5.7 to 6.1 THz, from 7.4 to 7.8THz, from 11.5 to 11.8THz, and from 13.3 to 13.5 THz was demonstrated in our experiment, and the result well matched the analysis. The maximum terahertz output energy was 1.61 μJ under the pump energy of 140 mJ, corresponding to the maximum THz wave conversion efficiency of 1.3 × 10~(-5), and the threshold pump energy is about 30 mJ.