Abstract

The energy scaling of THz wave in wide range based on surface-emitted (SE) ring-cavity terahertz parametric oscillator (TPO) with pump recycling technique have been demonstrated. The tunable range of 1.38 to 3.42 THz was achieved. Comparing with the conventional SE ring-cavity TPO, the upper limit of the tuning frequency range expanded from 2.46 THz up to 3.42THz, and a dramatic THz output energy and conversion efficiency increased more than 7 times in the entire tuning range. The maximum enhancement ratios of the terahertz wave output power were 10.3 times at 1.38 THz. And the average enhancement ratio of 8.4 times was achieved under the pump energy of 110 mJ/pulse in the entire tuning range. Moreover, the enhancement of TPO output by pump recycling can be attributed to the threshold reduction of the stimulated polariton scattering (SPS) process and the interaction improvement between the pump and Stokes waves in the difference frequency generation (DFG) process.

© 2018 The Author(s)