Strongly opalescent liquid network formed in a porous silicon matrix

We report on a medium exhibiting extremely efficient light scattering properties: a liquid network formed in a porous silicon matrix. We find that the scattering efficiency depends strongly on the filling factor of the liquid in the pores, its dielectric constant, and the type of termination of the internal surface of the layer. The spectral dependence of the scattering length of photons evidences the fact that the phenomenon is governed by a Mie-type scattering mechanism. The mean free path of photons in this medium is found to be in the micrometer range. (C) 2002 American Institute of Physics.