  Optical phase-array antennas can be used to control not only the angular
distribution but also the polarization of fluorescence from quantum emitters.
The emission pattern of the resulting system is determined by the properties of
the antenna, the properties of the emitters and the strength of the
antenna-emitter coupling. Here we show that Fourier polarimetry can be used to
characterize these three contributions. To this end, we measured the angle and
Stokes-parameter resolved emission of bullseye plasmon antennas as well as
spiral antennas excited by an ensemble of emitters. We estimate the
antenna-emitter coupling on basis of the degree of polarization, and determine
the effect of anisotropy in the intrinsic emitter orientation on polarization
of the resulting emission pattern. Our results not only provide new insights in
the behavior of bullseye and spiral antennas, but also demonstrate the
potential of Fourier polarimetry when characterizing antenna mediated
fluorescence.
