Investigation on the polarization characteristics of several crystals at terahertz band

Terahertz time-domain spectroscopy (THz-TDS) technology has developed rapidly in the past decades, and it has become an important method in the field of spectral analysis. Traditional THz-TDS can only analyze isotropic materials. But the need to add polarization analysis in THz-TDS is becoming more and more urgent. In this paper, a polarization THz-TDS system is established. The birefringence and polarization dependent loss parameters of YVO4, Iceland spar, MgF2, quartz in the terahertz band had been measured. Among them, the birefringence parameter of quartz, MgF2 and Iceland spar at 0.9 THz is in good agreement with the literature. The minimum polarization dependent loss of the four crystals between 0.2THz and 1.5THz are 3.03dB, 4.42dB, 4.4dB and 2.94dB, respectively.