Stabilization of a blue phase by a guest component: an approach based on a Landau-de Gennes theory

We discuss, with the aid of numerical calculations based on a Landau-de Gennes theory, the stabilization of a blue phase in chiral liquid crystals by introducing a guest component. Our argument is based on a common speculation that cores of disclination lines with higher free-energy density are replaced by the guest component. We assume that the guest component forms sharp interfaces with the liquid crystal (strong segregation). We show that, by a suitable choice of materials with small interfacial tension, a guest component of volume fraction less than 10% drastically increases the temperature range of thermodynamic stability of a blue phase, in agreement with experiments [Kikuchi, Nature Mater. 1, 64 (2002)].