Tailoring the surface plasmon resonance of embedded silver nanoparticles by combining nano- and femtosecond laser pulses

5 pags.; 4 figs.We demonstrate that the broad surface plasmon resonance (SPR) of a single layer of near-coalescence silver nanoparticles (NPs), embedded in a dielectric matrix can be tailored by irradiation with a single nanosecond laser pulse into a distribution featuring a sharp resonance at 435 nm. Scanning electron microscopy studies reveal the underlying mechanism to be a transformation into a distribution of well-separated spherical particles. Additional exposure to multiple femtosecond laser pulses at 400 nm or 800 nm wavelength induces polarization anisotropy of the SPR, with a peak shift that increases with laser wavelength. The spectral changes are measured in-situ, employing reflection and transmission micro-spectroscopy with a lateral resolution of 4 μ m. Spectral maps as a continuous function of local fluence can be readily produced from a single spot. The results open exciting perspectives for dynamically tuning and switching the optical response of NP systems, paving the way for next-generation applications. © 2014 AIP Publishing LLC.This work has been supported by the Spanish Ministry of Economy and Competitiveness (MAT2009-14282-C02-01, TEC2011-22422, and TEC2012-38901-C02-01). J.D. acknowledges support from the ERASMUS placement program, G.B. a grant from the CSIC-JAE predoctoral program, co-funded by the European Social Fund, and J.H.-R. a grant from the Spanish Ministry of Science and InnovationPeer Reviewe