Terahertz polarization determination by passive control of vectorial vortex beam

We demonstrate Terahertz polarization determination by the passive control of THz vectorial vortex (TVV) beams which is achieved from a THz achromatic-axially symmetric waveplate (TAS) based on total internal reflection in the 0.1-1.6 THz region. The polarization determination is demonstrated by analyzing the spatial intensity distribution in a THz image, and is applied two different THz sources at 0.16 and 0.36 THz, experimentally. Consider the inverse problem of linear system, it is also possible to determine the angularly variant polarization of TVV beam after passing through TAS plate.