Lattice vibrations of mineral and polarization dependence of material in a slit using terahertz waves

Abstract

Terahertz time-domain spectroscopy was used to probe the optical constants of natural mineral com- pounds and the polarization dependence of material confined in a sub-wavelength metal slit. The experimental results show that dolomite is a promising candidate as THz optical element material and seraphinite exhibits lattice vibrations at 0.96 THz whose mode is analyzed by the Kurosawa formula. The abnormal behavior predicted by Bethe’s diffraction theory is also experimentally observed from the vanishing in absorption from $\alpha$-lactose in the slit.