Light-controlled nanoswitches: from fabrication to photoelectric switching

Plasmon-assisted optical growth significantly improves the controllability of polymerization on the nanoscale, which greatly facilitates the fabrication of nanodevices and their integration. Traditional approaches for nanodevices strongly rely on nanofabrication techniques, which involve complicated multi-steps and expensive instrumentation. Here, we build photoelectric nanoswitches by precisely implanting photoelectric active polymers, polypyrrole, into metallic bowtie nanogaps via charge transfer induced oxidative polymerization, which show conductivity up to 4 μS m^-1 with an optical switching response time of ∼50 ms. We further demonstrate their photoelectric switchability with different laser powers, wavelengths and amounts of polypyrrole in the gaps. This plasmon-assisted optical growth strategy not only provides a facile and accurate means to control the polymerization process, but also greatly expedites the fabrication of nanodevices and their integration.