Large enhancement of nonlinear optical response in a hybrid nanobiomaterial consisting of bacteriorhodopsin and cadmium telluride quantum dots

We report wavelength-dependent enormous enhancement of the nonlinear refractive index of wild-type bacteriorhodopsin in the presence of semiconductor quantum dots. The effect is strongest in the region just below the absorption edge of both constituents of this hybrid material and in samples that show strong Förster resonance energy transfer. We show that enhancements of up to 4000% can be achieved by controlled engineering of the hybrid structure involving variations of the molar ratio of the constituents. This new hybrid material with exceptional nonlinear properties will have numerous photonic and optoelectronic applications employing its photochromic, energy transfer, and conversion properties. © 2013 American Chemical Society.This work was funded by the Irish Research Council for Science, Engineering, and Technology (ICSET) under the Embark Initiative and by Science Foundation Ireland under Grant No. 08/IN.1/I1862. Partial support of the Ministry of Higher Education and Science of the Russian Federation under the Contract Nos. 8842 and 11.G34.31.0050 is also acknowledged.Peer Reviewe