Thermomechanical mechanism of orientational optical nonlinearity in twisted nematic liquid crystals.

In a nonuniform nematic liquid crystal director reorientation may take place as a result of a temperature gradient. We formulated a two-dimensional model of the temperature gradient caused by the light absorption of a Gaussian laser beam impinging normally on the liquid crystal cell. Within this model, we calculated the director reorientation and the subsequent optical nonlinearity of the liquid crystal. [ABSTRACT FROM AUTHOR]