Mathematical Biology Seminar

Sartok Sircar
University of South Carolina
Friday Feb. 6, 2008
3:05pm in LCB 215
"Orientational dynamics of biaxial liquid crystals

Abstract: In 2004, a new "biaxial phase" of liquid crystalline polymer (LCP) was discovered experimentally. Since then, a lot of effort has been devoted at the experimental level to understand the orientational response of such a system in the presence of an external field. To our knowledge, for the first time, we numerically predict and present the various phases of biaxial LCPs and show the sequence of orientations in the different material parameter regions. The talk is divided into two sections. First, we present the steady-state nematics of a simpler class of uniaxial (or spheroidal) LCPs in the presence of an external field, state some theorems regarding the existence of the "solutions" and present the phase bifurcation diagram of the order parameters of these anisotropic systems. The flow-phase sequence of the biaxial (or cuboidal shaped) liquid crystals, in the presence of an external shear flow, are then discussed. The underlying hydrodynamic theory; as well as; the rheological properties are also presented.