| Organic phoorefractive (PR) composites have recently emerged as an important class of materials for applications including high-density data storage, optical communication, and biomedical imaging. In an effort to further improve their performance, this study focused on the utilization of functionalized semiconductor nanocrystals to photosensitize triaryamine (TPD)-based PR composites, as well as the application of TPD-based PR composites in the restoration of aberrated optical information. A novel approach to functionalize CdSe quantum dot (QCdSe) was firstly introduced where the sulfonated triarydiamine (STPD) was used as charge-transporting ligand to passivate QCdSe. TPD-based photoconductive and PR composites were photosensitized with the STPD-passivated QCdSe (SQCdSe). Due to the charge-transporting capability of STPD, the composites photosensitized with STPD-capped QCdSe exhibited superior performance relative to composites employing more traditional photosensitizers (such as fullerene C60 and trioctylphosphine-capped QCdSe), with figures-of-merit including photoconductivities in excess of 60 pS/cm, two-beam coupling gain coefficients in excess of 110 cm-1, and PR response time of less than 30 ms. In addition, the ability of TPD-based PR composites to correct aberrations associated with a laser beam was described. Here, a severely aberrated laser beam was able to be restored to a nearly unaberrated condition through the PR process, and the potential of this technique for practical applications was well explained. Based on the current experimental geometry, a PR response time of 0.5 s was observed, which is the fastest PR response time reported for a PR composite operating under experimental conditions designed for the correction of optical aberrations. |
