Observation of anisotropic emission from semiconductor quantum dots in nanocomposites of metal nanoparticles

Colloidal semiconducting quantum dots ( QDs), also known as nanocrystals, offer a number of advantages in light generation, e.g., for solid-state lighting, biol ogical labeling, and bio -imaging.
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These applications typically necessitate high quantum eff iciencies in film, preferably with polarized emission in certain applications. One of the major problems encountered when working with films of these QDs is the decrease in their fluorescence quantum efficiency in the solid form. Another technical challenge is to obtain anis otropic emission from these QDs. Recently plasmonics has enabled a wide range of important applications related to nanocrystals including metal enhanced light generation and plasmonic biosensing.
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In this work, to address the se difficulties encountered with QD solids, we investigate and demonstrate anisotropic enhanced emission from semiconductor quantum dots placed in multilayered plasmon resonator nanocomposite s using strong plasmon-exciton interactions. In these metal nanoparticle (MNP) resonator architectures, we show that highly isotropic nature of QD emission c an desirably be altered through modifying emission kinetics by plasmon coupling, while also enhancing the overall QD emission.