Tuning the optical properties of gold nanostructures fabricated on flexible substrates

In this paper we present a laser-based method for metal nanostructures formation on flexible substrates. The analysis of the obtained structures is focused on their optical properties. The nanostructures are fabricated by laser processing of gold thin films. The films are deposited on PMMA and PVC substrates by classical PLD technology. The produced films are then annealed by nanosecond pulses delivered by Nd:YAG laser system operated at λ = 355 nm. At certain conditions the laser treatment leads to formation of discrete nanostructure on the substrate surface. The optical properties of samples fabricated at different conditions are examined by optical spectroscopy. Bending of the substrates at different angles is used to modify the characteristics of the produced structure which leads to change of its optical properties. In this way the plasmon band of the obtained nanostructures can be efficiently tuned in a range of about 30 nm. The experiments of using produced structures in Surface Enhanced Raman Spectroscopy show that they can be an efficient alternative of the already developed.