Optical manipulation of nematic colloids at the interfaces in azo-dye-doped liquid crystals

This study demonstrates the optical manipulation of colloids dispersed in an azo-dye-doped liquid crystals (DDLC) where the accumulation occurs at the interfaces of the phase domains. We explain the mechanism related to the formation of the domains and the movement of the colloids in DDLCs with respect to the isomerization of azo-dye molecules via the illumination of laser beams. The colloids are dragged to the interfaces of the isotropic/nematic domain (IN) and the air bubble/isotropic domain (AI) by molecular interaction and Marangoni flows.