Multiple-beam output of a surface-emitted terahertz-wave parametric oscillator by using a slab MgO:LiNbO_3 crystal

Abstract

A MgO:LiNbO₃ slab configuration for the surface-emitted terahertz-wave parametric oscillator (TPO) is presented. The pump and the oscillating Stokes beams were totally reflected at the slab surface and propagated zigzaggedly in the slab MgO:LiNbO₃ crystal. Up to five terahertz beams were emitted perpendicularly to the surface of the crystal. The total output energy of the five THz-wave beams was 3.56 times as large as that obtained from the conventional surface-emitted TPO at the same experimental conditions. The intensity distributions of the THz wave beams were measured, and they were unsymmetrical in the horizontal direction while symmetrical in the vertical direction.

Injection-Seeded Terahertz Parametric Oscillator with a Ring-Cavity Configuration

“…The process of SPS must obey the energy conservation (ω P = ω S + ω T ) and momentum conservation (k P = k S + k T ), where ω P , ω S , and ω T are the frequencies of the pump, Stokes, and THz waves, respectively, and k P , k S , and k T are the wave vectors of the three waves. By employing slowly varying envelope approximation, the coupled-wave equations of the THz wave in the y direction of the nonlinear crystal can be expressed as [20] n T c…”

Enhancement of Intracavity-Pumped Terahertz Parametric Oscillator Power by Adopting Diode-Side Pumped Configuration Based on KTiOPO4 Crystal

“…This is the first time that a nonlinear medium different from the traditional crystal LiNbO 3 (LN) was realized to generate THz radiation based on SPS. Different from the THz frequency of 0.6-3.5 THz obtained from the LN crystal [16][17][18][19][20], the generated THz frequency could be tuned from 3.17 THz to 6.13 THz by using the KTP crystal. The obtained THz pulse energy was 336 nJ at 5.72 THz when the pulse repetition frequency (PRF) was 10 Hz and the pump pulse energy was 80 mJ [11].…”

Optical rectification in 4H-SiC: paving the way to generate strong terahertz fields with ultra-wide bandwidth

“…Organic crystals possess extremely high nonlinearity and can produce strong terahertz pulses within one coherent length, represented by DAST and BNA [18,19] , but they are usually excluded by robust systems because of deliquescence, a low LIDT and serious terahertz absorption [22] . As a popular crystalline material in nonlinear optics, lithium niobate (LiNbO 3 ) has a wide bandgap and a high nonlinear coefficient and LIDT [28,29] , enabling widely tunable terahertz generation via stimulated polariton scattering [29][30][31] . However, LiNbO 3 -based OR was unachievable for a long time due to the difficulty in PM [22] , until the tilted-pulse-front (TPF) technique was proposed.…”