Measurement of the Dielectric Constant of Optically Dense Materials by Polarization-Sensitive Terahertz Ellipsometry

We constructed a terahertz ellipsometry that can measure both transversal electric field components simultaneously. To illustrate the reliability of this system, we measured a Si wafer with a resistivity of 0.05Ω.cm which is an optically dense material in THz band. The simultaneous detection of the orthogonal components shows a well precision of the dielectric constant. The difference between the experimental data and the Drude model means imperfect qualities of the optical elements and the accuracy of the system should be improved by some calibration ways.