Ferroelectric Liquid Crystals: Realities and Possibilities

Rolfe G. Petschek, Case Western Reserve University

Ferroelectric liquid crystals are of scientific interest, as they have interesting, unusual broken symmetries. They are also of applied interest as the non-crystalline, easily processible characteristics of liquid crystals together with the large response to electric fields implied by ferroelectricity suggest a variety of useful devices. Ferroelectric liquid crystals are currently used in some laser printers and have been suggested as the active materials in displays, second-order non-linear optical materials, and "soft" or muscle-like actuators. These latter possibilities have not been realized extensively—or in some cases at all—commercially despite (in the case of displays) billion dollar investments. I will review the various ways in which people have proposed to make, claimed to make, or succeeded in making ferroelectric liquid crystals. I hope to convey why it is difficult to make phases which have these particular broken symmetries, particularly if it is also desirable to tailor the materials properties in other ways. I will discuss in some detail a recent idea for the formation of ferroelectric nematic phases and gels. These last mentioned phases might be useful in soft actuators.

The P/T Colloquium is
typically held each
Thursday, 3:45–5:00 PM.
Refreshments are served
at 3:15 PM.