  We provide a detailed discussion on the electromagnetic modeling and
classification of polarization converting bianisotropic metasurfaces. To do so,
we first present a general approach to compute the scattering response of such
metasurfaces, which relies on a generalized sheet transition conditions based
susceptibility model. Then, we review how the fundamental properties of
reciprocity, energy conservation, rotation invariance and matching may be
expressed in terms of metasurface susceptibilities and scattering parameters,
and show how these properties may affect and limit the polarization effects of
metasurfaces. Finally, we connect together the metasurface susceptibility model
to the structural symmetries of scattering particles and their associated
polarization effects. This work thus provides a detailed understanding of the
polarization conversion properties of metasurfaces and may prove to be of
particular interest for their practical implementation.
