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

The anisotropic metal nanoparticles are effective nanoprobes for optical imaging due to their sensitive nonlinear plasmonic responses, but the associated photothermal instability issues have hindered their further application potentials. In this letter, we reported the superresolution imaging and optical memory via suppression of the plasmonic scattering of core-shell gold nanorods (GNRs). Good thermal stability and conductivity from GNRs coated with 20 nm silica shell supported the superresolution imaging with a lateral feature size of 114 nm (λ/5.6) via a low suppressing laser power (0.9 mW). Furthermore, we realized the superresolution imaging of the GNRs doped inside a bio-cell sample with a feature size of 128 nm (λ/5) and the sub-diffraction optical recording with a feature size as small as 173 nm in a GNRs-polyvinyl alcohol sample. This work further extends our understanding as well as the application of core-shell anisotropic metal nanoparticles based on nonlinear plasmonic scattering.