  Light echoes of debris disks around active stars can reveal disk structure
and composition even when disks are not spatially resolved. Unfortunately,
distinguishing reflected light from quiescent starlight and unexpected
post-peak flare structure is challenging, especially for edge-on geometries
where the time delay between observed flare photons and light scattered from
the near side of the disk is short. Here, we take advantage of the fact that
scattered light from a dusty disk is polarized, depending on the location of
the scattering site and the orientation of the disk relative to a distant
observer. Filtering reflected light into its polarized components allows echoes
to stand out in predictable ways. We test this idea with a simple model for a
disk around an active M dwarf. Our results demonstrate that the use of
polarimetric data of flaring stars can significantly enhance echo signals
relative to starlight and yield more robust and accurate fits to disk
parameters compared to analyses based on the total intensity alone.
