Photonic scattering materials, such as biological tissue and white paper, are
made of randomly positioned nanoscale inhomogeneities in refractive index that
lead to multiple scattering of light. Typically these materials, both
naturally-occurring or man-made, are formed through self assembly of the
scattering inhomogeneities, which imposes challenges in tailoring the disorder
and hence the optical properties. Here, We report on the nanofabrication of
photonic scattering media using direct laser writing with deterministic design.
These deterministic scattering media consist of submicron thick polymer
nanorods that are randomly oriented within a cubic volume. We study the total
transmission of light as a function of the number density of rods and of the
sample thickness to extract the scattering and transport mean free paths using
radiative transfer theory. Such photonic scattering media with deterministic
and controllable properties are model systems for fundamental light scattering
in particular with strong anisotropy and offer new applications in solid-state
lighting and photovoltaics.Comment: 18 pages, 9 figure