Electrical and optical properties of polyacetylene film in THz frequency range

Electrical and optical properties such as power absorption, index of refraction, and complex conductivity of polyacetylene film are determined by transmission measurement using a source of freely propagating subpicosecond pulses of THz electromagnetic radiation and without invoking the Kramers-Kronig relationships. Four types of polyacetylene samples, undoped pristine, FeCl4− doped pristine, undoped and stretched twice, and FeCl4− doped and stretched twice, are compared experimentally. The undoped pristine polyacetylene is found to have a resonance of 2.45 THz. The stretched polyacetylene have an angle-dependent curve along the direction of the polarized THz beam.