  The longitudinal components of orthogonal-circularly polarized fields carry a
phase singularity that changes sign depending on the polarization handedness.
The addition of orbital angular momentum adds to or cancels this singularity
and results in polarization-dependent scattering through round and square
apertures, which we demonstrate analytically, numerically, and experimentally.
By preparing the incident polarization and arranging the configuration of
sub-wavelength apertures, we produce shadow-side scattered fields with
arbitrary phase vorticity.
