Fourier transform infrared absorbance and photoluminescence spectroscopy studies of CdSe colloidal quantum dot/conducting polymer nanocomposites for application to infrared photodetectors

In this paper we investigate the optical properties of four CdSe colloidal quantum dot/conducting polymer nanocomposites deposited on GaAs substrates using photoluminescence and Fourier transform infrared absorbance. The purpose of this investigation is to find an appropriate electron-conducting polymer for use in a photoconductor that utilizes intraband transitions in the conduction band to detect mid- to long-wave-infrared radiation. As a feasibility demonstration, we fabricate a two-terminal photoconductor and characterize its dark current and spectral responsivity (at 125 K), demonstrating intraband peaks at 0.465 and 0.527 eV, which correspond to 2.67 and 2.35 μm. © 2007 Materials Research Society.