Observation of Newtonian Capillary Shear Flow in an Oriented Cholesteric Liquid Crystal

Newtonian capillary shear flow was observed for the first time in a cholesteric liquid crystal with the helix axis perpendicular to the flow. The effective viscosity in the cholesteric phase had a magnitude comparable to the viscosity of the isotropic liquid extrapolated to the cholesteric temperature. Oscillatory pitch dependence of the viscosity was seen when the pitch length was comparable to the capillary width.