Hybrid quantum-dot-polymer nanocomposites for infrared photorefractivity at an optical communication wavelength

The efficient photoconductivity and photorefractive response (PR) at the infrared wavelength of 1550nm of a polymeric nanocomposite with colloidally fabricated PbSe semiconductor quantum dots as the photoactive constituent, was analyzed. The photoconductor, poly(N-vinylcarbazole) (PVK), was used as the primary continuous matrix for the transport of photogenerated charge carriers. To demonstrate infrared PR response in the composites, two-beam coupling (TBC) and degenerate four-wave mixing (DFWM) experiments were performed employing standard tilted geometry. The results show that the photoresponse of a polymeric nanocomposite device was extended to the 1550 nm telecommunications band using size tunable absorption of semiconductor quantum dots.