Simultaneous positive and negative optical patterning with dye-sensitized CdSe quantum dots

J Chem Phys. 2019 Oct 14;151(14):141102. doi: 10.1063/1.5124232.

Abstract

CdSe quantum dots are functionalized with the organic dye iron β-tetraaminophthalocyanine to reward a solution-processable hybrid material with two individually addressable optical resonances. We exploit this dual functionality during optical write/optical read patterning experiments and show that it is possible to simultaneously write complex optical patterns with positive and negative fluorescence contrast. This is enabled by a fluorescence enhancement under near-resonant excitation of the quantum dots in combination with a fluorescence bleaching during excitation of the singlet transition of the phthalocyanine. The presence of the organic dye not only enables negative optical patterning but also enhances the contrast during positive patterning. Furthermore, the patterning result is strongly dependent on the excitation wavelength during readout. Our results highlight the new possibilities that arise from combining inorganic quantum dots and organic π-systems into hybrid nanocomposites.