円錐螺旋状スメクチックC相とネマチック相の理論

抄録

A mean-field theory is introduced to describe heliconical nematic (NTB), heliconical smectic-C (SmCTB), and biaxial heliconical smectic-C (SmCTB,b) phases with mirror symmetry breaking. We extend our previous theories of the NT B phase to the heliconical smectic-C phases, by taking into account one-dimensional spatial ordering of smectic layers. The calculated phase diagrams on the temperature–alkyl chain length plane show a rich variety of phase transitions: first- and second-order NTB-SmCTB transitions, etc., including tricritical, tetracritical, and multicritical points. Our theory is qualitatively consistent with an experimental phase diagram.