  A novel method for single-step, lithography-free, and large-scale laser
writing of nanoparticle-based plasmonic structures has been developed. Changing
energy of femtosecond laser pulses and thickness of irradiated gold film it is
possible to vary diameter of the gold nanoparticles, while the distance between
them can be varied by laser scanning parameters. This method has an advantage
over the most previously demonstrated methods in its simplicity and
versatility, while the quality of the structures is good enough for many
applications. In particular, resonant light absorbtion/scattering and
surface-enhanced Raman scattering have been demonstrated on the fabricated
nanostructures.

Optics