  Simple high-performance two-stage hybrid technique was developed for
fabrication of different plasmonic nanostructures, including nanorods,
nanorings, as well as more complex structures on glass substrates. In this
technique a thin noble metal film on a dielectric substrate is irradiated by a
tightly focused single nanosecond laser pulse and then the modified region is
slowly polished by an accelerated argon ion (Ar+) beam. As a result, each
nanosecond laser pulse locally modifies the initial metal film through
initiation of fast melting and subsequent hydrodynamic processes, while the
following Ar+-ion polishing removes the rest of the film, revealing the hidden
topography features and fabricating separate plasmonic structures on the glass
substrate. We demonstrate that the shape and lateral size of the resulting
functional plasmonic nanostructures depends on the laser pulse energy and metal
film thickness, while subsequent Ar+-ion polishing enables to vary height of
the resulting nanostructures. The plasmonic properties of the fabricated
nanostructures were characterized by dark-field micro-spectroscopy, Raman and
photoluminescence measurements from single nanofeatures, as well as by
supporting numerical calculations of the related electromagnetic near-fields
and Purcell factors. The developed simple two-stage technique represents a next
step towards direct large-scale laser-induced fabrication of highly-ordered
arrays of complex plasmonic nanostructures.
