Hybrid nanoplasmonics is a recent and promising branch of research, that attempts to control the energy transfer between nano-emitters and surface plasmons. Colloidal quantum dots are good emitters due to their unique set of optical properties. In our work, quantum dots were excited in close proximity to a silver nanowire and the quantum dot emission was transferred into guided propagating nanowire surface plasmons (SPs) that were scattered at the nanowire end. Compared with metallic nanoparticles, silver nanowires enable the propagation of SPs in a well-defined direction along the nanowire axis, allowing for long-distance energy transfer between the nano-emitter and a specific nanowire point of interest. The challenge related to this promising hybrid system is to control the position of quantum dots on the nanowire. Our approach of nano-emitters positioning is based on two-photon photopolymerization of a photosensitive material containing quantum dots. This approach allows one to use light for positioning the quantum dots on the plasmonic nanosystem in a controlled manner. We report on a new controlled hybrid plasmonic nanoemitter based on coupling between quantum dots and propagating surface plasmons that are supported by silver nanowires, considered as surface plasmons resonators and observed through their scattering at the nanowire ends. A parametric study of the distance between the quantum dots and the nanowire extremity shows that precise control of the position of the launching sites enables control of light intensity at the wire end, through surface plasmon propagation length. This new approach is promising to produce efficient acceptor-donor hybrid nano-systems.
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