Abstract
The optical properties of dielectric materials with subwavelength cylindrical pores are commonly described by effective medium models. We compare the Maxwell Garnett and the Bruggeman effective medium model for porous silicon with simulations to study their applicability. We found that the Maxwell Garnett model matches the results of the simulations even up to high porosities and discuss the reasons for this. We advocate using this model for membranes with cylindrical pores in the future.