Polarization dependence of the permanent deformation of silver nanoparticles in glass by ultrashort laser pulses
Martin-Luther-Universität Halle-Wittenberg, Fachbereich Physik, 06099 Halle, Germany
2 Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, 06120 Halle, Germany
Corresponding author: a email@example.com
Published online: 15 September 2001
Glass containing spherical silver nanoparticles has been irradiated with single, intense, ultrashort laser pulses, with a wavelength corresponding to the surface plasmon resonance of the particles. After irradiation with linear polarization, dichroism is observed. Transmission electron microscopy studies reveal that these spectral changes are caused by deformation of the particles to anisotropic (in the TEM projection approximately ellipsoidal) shapes with an additional halo of small silver particles around the central one. The deformed particles are uniformly oriented with their longer axes perpendicular to the laser polarization. Using laser pulses with circular polarization, again a halo is formed around the particles, but the central particles remain spherical, and no dichroism was observed in the optical spectra.
PACS: 61.46.+w – Nanoscale materials: clusters, nanoparticles, nanotubes and nanocrystals / 81.40.Tv – Optical and dielectric properties (related to treatment conditions)
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2001