Conjugate Polymer Induced Enhancement of THz Radiation in Semiconductors

Abstract

Conjugate polymer induced enhancement of terahertz radiation is observed for the first time in this report. Terahertz radiation (THz) from the surfaces of various semiconductor wafers and microstructures is studied. The intensities of the THz radiation from the surfaces of certain semiconductors with a thin layer of conjugate polymer (2, 3-dibutoxy-1, 4-polyphenylenevinylene (DB-PPV)) deposited on their surfaces are greatly enhanced. The enhancement of THz radiation depends on the mechanism of inducting the THz radiation. Modulation spectroscopy of photoreflectance (PR) is employed to investigate the change in the built-in electric field and surface or interface state densities, which are closely related to the enhancement of the THz radiation.