Plasmon-enhanced photothermal response in heterogeneous metallic trimers

Heat generation in plasmonic nanostructures has attracted enormous attention due to the ability of these nanostructures to generate high temperatures in nanoscale volumes using far-field irradiation, enabling applications ranging from photothermal therapy to fast (sub-nanosecond) thermal optical switching. Here we investigate the optical and thermal response of a heterogeneous trimer structure composed of a gold nanoparticle surrounded by two larger silver nanoparticles analytically and numerically. We observe that this type of multi-scale multi-material plasmonic oligomer can produce temperature changes over two orders of magnitude higher than possible with isolated gold nanoparticles.