  One of the central experimental efforts in nematic colloids research aims to
explore how the interplay between the geometry of particles along with the
accompanying nematic director deformations and defects around them can provide
a means of guiding particle self-assembly and controlling the structure of
particle-induced defects. In this work, we design, fabricate, and disperse
low-symmetry colloidal particles with shapes of spirals, double spirals, and
triple spirals in a nematic fluid. These spiral-shaped particles, which are
controlled by varying their surface functionalization to provide tangential or
perpendicular boundary conditions of the nematic molecular alignment, are found
inducing director distortions and defect configurations with non-chiral or
chiral symmetry. Colloidal particles also exhibit both stable and metastable
multiple orientational states in the nematic host, with a large number of
director configurations featuring both singular and solitonic nonsingular
topological defects accompanying them, which can result in unusual forms of
colloidal self-assembly. Our findings directly demonstrate how the symmetry of
particle-generated director configurations can be further lowered, or not, as
compared to the low point group symmetry of solid micro-inclusions, depending
on the nature of induced defects while satisfying topological constraints. We
show that achiral colloidal particles can cause chiral symmetry breaking of
elastic distortions, which is driven by complex three-dimensional winding of
induced topological line defects and solitons.
