  In this work, we show that Janus washers, genus-one colloids with hybrid
anchoring conditions, form topologically required defects in nematic liquid
crystals. Experiments under crossed polarizers reveal the defect structure to
be a rigid disclination loop confined within the colloid, with an accompanying
defect in the liquid crystal. When confined to a homeotropic cell, the
resulting colloid-defect ring pair tilts relative to the far field director, in
contrast to the behavior of toroidal colloids with purely homeotropic
anchoring. We show that this tilting behavior can be reversibly suppressed by
the introduction of a spherical colloid into the center of the toroid, creating
a new kind of multi-shape colloidal assemblage.
