Strain Effects on the Optical Properties of Metal Nanoparticles

We have recently been studying the effects of strain on the optical properties of metal nanoparticles, which have become of significant interest to the materials, physics, biology and chemistry communities due to the fact that they exhibit unique optical properties, specifically surface plasmon resonance and surface enhanced raman scattering, which are being used primarily for optical sensors at the single molecule level, but for many other applications, including photothermal cancer treatment and optical imaging.  While strain engineering of bandstructure in semiconductors is a well-established and important area, similar types of studies on metals have not been performed despite the immense potential of metal nanoparticles.  We have performed such fundamental studies of strain effects on gold nanospheres, with the results having been accepted for publication in Journal of the Mechanics and Physics of Solids (http://dx.doi.org/10.1016/j.jmps.2009.12.001).  The basic finding is that both the plasmon resonance wavelength, as well as the magnitudes of the plasmon resonance and surface enhanced raman scattering, can all be tuned and enhanced using mechanical strain.