Abstract

It is known that nematogenic materials such as MBBA and 5CB can have a very large nonlinear refractive index in the isotropic phase due to pretransitional local ordering. However there does not appear to have been any systematic experimental study of the factors which affect the size of the nonlinearity for different molecular structures. In this paper we report on experiments in which we have used degenerate four-wave mixing to measure the magnitude of the nonlinear susceptibility and its time constant for a number of different materials in various conditions.

© 1985 Optical Society of America