Electrophoresis of metal-dielectric Janus particles with dipolar director symmetry in nematic liquid crystals

Abstract

We study electrophoresis of metal-dielectric Janus particles with dipolar director symmetry in two nematic liquid crystals (LCs) having same sign of conductivity anisotropy (∆σ) but opposite sign of dielectric anisotropy...

Nontrivial electrophoresis of silica nano and microrods in a nematic liquid crystal

“…We would like to make some comment here. In our system the Reynolds number Re = rva/Z C 10 À7 and Ericksen number Er = Zva/K C 10 À2 , 38 hence the fluid inertia is negligibly small and the director configuration around the particles remain unaffected by the flow. Also, as in ref.…”

“…These values are closer to that were reported for spherical dipolar particles. 38 Fig. 9(b) shows the variation of tilt angle (y) with applied electric field.…”

Design and Preparation of Nematic Colloidal Particles

“…Surface interactions on colloidal particles’ surface allow for the activation of their translational or rotational motion due to facile response to light − or other external stimuli. , Among the key features allowing the transformation of passive colloidal inclusions into micromotors and micromachines are functionalization of azobenzene dye molecules on the surface of colloidal particles ,− or using azobenzene dyes in the anisotropic nematic fluid host. ,− ,− …”

“…Surface interactions on colloidal particles' surface allow for the activation of their translational or rotational motion due to facile response to light 106−110 or other external stimuli. 111,112 Among the key features allowing the transformation of passive colloidal inclusions into micromotors and micromachines are functionalization of azobenzene dye molecules on the surface of colloidal particles 105,113−115 or using azobenzene dyes in the anisotropic nematic fluid host. 106,100−108,116−123 When it comes to designing and synthesizing azobenzene dye to be functionalized on the particle surface, one needs to keep in mind that the azobenzene dye should be robustly attached onto the surface and needs to readily respond to light within a viscous nematic medium.…”

Topological defect-propelled swimming of nematic colloids

“…For example, electrophoretically driven colloids move along or perpendicular to the director field, made possible by the fluid’s dielectric anisotropy ( 34 , 35 ). Electrophoretically driven motion of Janus beads with metallic hemispheres have been studied to enhance the broken symmetry ( 36 , 37 ). Electric field–driven flow fields have also been harnessed; electrohydrodynamic rolls oriented within NLC have been exploited to direct the formation and motion of functional assemblies ( 38 ).…”