Optical vortex induced microdroplet with a plasmonic nanocore

We demonstrate the creation of a microdroplet with a plasmonic Au nanoparticle core by employing the optical vortex laser-induced forward transfer technology. The single plasmonic nanoparticle in the microdroplet is printed as a plasmonic nanocore on a receiver substrate with a spatial resolution beyond the diffraction limit. This phenomenon manifests that the optical vortex traps three-dimensionally only a suspended single Au nanoparticle in its dark core by its repulsive force owing to plasmonic resonance, and it has the potential to realize a myriad of plasmonic structured materials.