Session D40 - Poster Session I.
POSTER session, Monday afternoon, March 12
Exhibit Hall, Washington State Convention Center
Anisotropy in the spatial dependence of multiply scattered transmitted light intensity in an oriented nematic phase as it is cooled towards the smectic A is measured. As shown by previous authors(H. Stark,M.H. Kao, K.A. Jester, A.G. Yodh, and P.J. Collings, J. Opt. Soc. Am. A 14 156 (1997).) these measurements allow the determination of the light diffusion constants parallel and perpendicular to the director. It has been suggested \footnote H. Starl and T.C. Lubensky Phys. Rev. E 55 514 (1996). that the transition to the weakly scattering smectic phase may be explored in a similar way. The diffusion constant depends on the ratio of elastic constants, of which the twist and bend constants diverge. We present data on the temperature dependence of the diffusion constant ratio and compare divergence of the elastic constants to standard models and methods.