Electrooptic response of liquid crystalline blue phases with different chiral pitches

The relationship between the electrooptic response properties and the chiral pitch of a blue phase was experimentally investigated. The Kerr constant was found to be proportional to the cube of the chiral pitch, although a theoretical square-law was expected. It was also revealed that the effect of the chiral pitch on the response time was dependent on the type of electric field-induced birefringence of the blue phase, such as local director reorientation and electrostriction. The response of the local director reorientation process was very fast at sub-millisecond and also proportional to the cube of the chiral pitch. However, in the case of the electrostriction process, the effect of the chiral pitch on the response time was insignificant and the response time was a few milliseconds.