Super-resolution optical imaging and memory enabled by scattering suppression of shell-coated gold nanorods

Owing to sensitive nonlinear plasmonic responses, anisotropic metal nanoparticles are effective nanoprobes for optical imaging. However, the photo-thermal instability issues have hindered their further nanophotonics application potentials. In this letter, we reported the super-resolution imaging and optical memory by suppressing the plasmonic scattering signal of core-shell gold nanorods (GNRs). Good thermal stability and conductivity from GNRs coated with 20 nm silica shell supported the super-resolution imaging with a lateral feature size of 114 nm (λ/5.6) via a very low suppressing laser power (0.9 mW). The GNRs were then employed for achieving super-resolved bioimaging with a feature size of 128 nm (λ/5). More importantly, we were able to realize the super-resolution optical recording (feature size: 173 nm) in a GNRs-polyvinyl alcohol sample. This work further extends our understanding of the nanophotonics application of core-shell anisotropic metal nanoparticles based on nonlinear plasmonic scattering.