Hongxiang Liu

Propagation Characteristics of Two-Dimensional Photonic Crystals in the Terahertz Range

Based on plane wave expansion method, the band gaps of a two-dimensional terahertz photonic crystal with a square lattice are optimized through varying structural parameters. The electromagnetic field distribution is accurately described for a terahertz photonic crystal splitter by finite difference time domain method.

Energy scaling and extended tunability of terahertz wave parametric oscillator with MgO-doped near-stoichiometric LiNbO_3 crystal

A widely tunable, high-energy terahertz wave parametric oscillator based on 1 mol. % MgO-doped near-stoichiometric LiNbO3 crystal has been demonstrated with 1064 nm nanosecond pulsed laser pumping. The tunable range of 1.16 to 4.64 THz was achieved. The maximum THz wave output energy of 17.49 μJ was obtained at 1.88 THz under the pump energy of 165 mJ/pulse, corresponding to the THz wave conversion efficiency of 1.06 × 10-4 and the photon conversion efficiency of 1.59%, respectively. Moreover, under the same experimental conditions, the THz output energy of TPO with MgO:SLN crystal was about 2.75 times larger than that obtained from the MgO:CLN TPO at 1.60 THz. Based on the theoretical analysis, the THz energy enhancement mechanism in the MgO:SLN TPO was clarified to originate from its larger Raman scattering cross section and smaller absorption coefficient.

Fast Terahertz Imaging based on Compressive Sensing

we demonstrate an active terahertz imaging method based on compressive sensing. With all modulation matrices engraved on one mask, the fast imaging has achieved. Recognizable result of letter “H” has obtained with PSNR of 10.21.