Terahertz vector beam generation using segmented nonlinear optical crystals with three-fold rotational symmetry

We demonstrated a new method of Terahertz cylindrical vector beam generation using segmented nonlinear crystals with three-fold rotational symmetry. The polarization dependent in-plane images obtained with a Terahertz camera clearly showed axial-symmetric polarization distributions. The electro-optic sampling image clearly visualized the longitudinal electric field at the focal point.