Local Fields' Localization and Chaos and Nonlinear- Optical Enhancement in Composites
نویسنده
چکیده
The paper is devoted to linear and nonlinear optical properties of disordered clusters and nanocomposites. Linear and nonlinear optical polarizabilities of large disordered clusters, fractal clusters in particular, and susceptibilities of nanocomposites are found and calculated numerically. A spectral theory with dipole interaction is used to obtain quantitative results. Major properties of systems under consideration are giant fluctuations and chaos of local fields that cause strong enhancement (by many orders of magnitude) of nonlinear optical responses. The enhancement and fluctuations properties of the local fields are intimately interrelated to the inhomogeneous localization of the systems’ eigenmodes (“plasmons”). Due to these fluctuations, mean-field theory completely fails to describe optical polarizabilities.
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