Possibility of a Field-Induced Hexagonal Blue Phase in Cholesteric Liquid Crystals

Phase diagrams of cholesteric liquid crystals in relatively weak electric or magnetic fields are calculated. In very weak fields the helicoidal-phase region grows at the expense of the cubic blue phases. A new phase, having a two-dimensional structure, is shown to appear at physically realizable chiralities for fields exceeding E70(Δε)1/2 kV/cm and H20(Δχ)1/2 Oe, where Δε(Δχ) is the dielectric (diamagnetic) anisotropy. This structure exists between the disordered and cubic-blue-phase regions in the phase diagram.