  Transparent glass ceramic materials, with microstructures comprised of
dispersed nanocrystallites in a residual glass matrix, offer the prospect of
nonlinear optical properties. However, good transparency requires low optical
scattering and low atomic absorption. The attenuation of light due to
scattering (turbidity) will depend upon the difference in refractive index of
the two phases and the size and distribution of crystals in the glass. Here, we
model the glass ceramic as a late-stage phase-separated structure, and compute
scattering in this model. We find that the turbidity follows a k^8 R^7
relationship, where k is the wavevector of light in the glass ceramic and R is
the average radius of the crystals in the glass.
