Article

Dispersion of nonlinear dielectric function of Au nanoparticles in silica glass

Quantum Beam Center, National Institute for Materials Science, 3-13 Sakura, Tsukuba, Ibaraki, 305-0003, Japan.
Optics Express (Impact Factor: 3.53). 06/2007; 15(10):6010-8. DOI: 10.1364/OE.15.006010
Source: PubMed

ABSTRACT We have investigated wavelength dispersion of photo-induced nonlinear dielectric function of Au nanoparticle materials. Transient transmission and reflection spectra were sequentially measured by the pump-probe method with a femtosecond laser system. The dispersion of real and imaginary parts of the nonlinear dielectric function of Au:SiO(2) nanoparticle material in the vicinity of the surface plasmon resonance was evaluated from these transient spectra with total differential. A local electromagnetic field factor and interband transition in Au nanoparticles directly dominate the dispersion.

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