(311a) Metal-Dielectric Nanocomposites For Solar Energy Applications

Composite materials consisting of metal nanoparticles embedded in host dielectric matrices exhibit novel optical properties due to the interaction of light with electrons at the metal-dielectric interface. For instance, the optical response of such a composite material may be tailored to the solar spectrum via the manipulation of parameters such as volume fraction, particle size, and particle spacing. Towards this end, we have developed ?mixing rules? or homogenization principles that allow for the accurate prediction of the effective dielectric constant of such materials [1]. Once such materials are designed based on plasmonic principles, technologies for their robust manufacturing need to be developed. We will show that a promising route towards the fabrication of such nanocomposites is laser-induced dewetting and self-organization in nanoscopic (1- 10 nm) metals films [2-6]. We will discuss experimental approaches for the synthesis of such nanocomposites, mathematical models for the prediction of the process thermal cycles and particle size/spacing and, homogenization approaches for the prediction of the wavelength-dependent absorption of light by such materials. This integrated approach enables the design of multi-metal nanocomposites which maximize absorption at wavelengths relevant to the solar spectrum.

1. H.G. Garcia, J. Trice, R. Kalyanaraman & R. Sureshkumar, Self-consistent determination of plasmonic resonances in ternary nanocomposites, Phys. Rev. B, 75, 1 (2007).

2. J. Trice, D.G. Thomas, C. Favazza, R. Sureshkumar & R. Kalyanaraman, Investigation of pulsed laser induced dewetting in nanoscopic metal films, in press, Phys. Rev. B. (2007) http://arxiv.org/abs/cond-mat/0609182

3. C. Favazza, R. Kalyanaraman & R. Sureshkumar, Robust nanopatterning by laser-induced dewetting of metal nanofilms, Nanotechnology, 17, 4429-34 (2006).

4. C. Favazza, J. Trice, H. Krishna, R. Kalyanaraman & R. Sureshkumar, Laser induced short and long range ordering of Co nanoparticles on SiO2, Appl. Phys. Lett. 88, 153118 (2006).

5. C. Favazaa, J. Trice, H. Garcia, R. Kalyanaraman & R. Sureshkumar, Nanoparticle ordering by dewetting of Co on SiO2, J. Electronic Materials, 35, 1618-20 (2006).

6. C. Favazza, J. Trice, R. Kalyanaraman and R. Sureshkumar, Self-organized metal nanostructures through laser driven thermocapillary convection, under review, http://arxiv.org/abs/0704.1179