Artículos de revistas
Tricritical-like behavior of the nonlinear optical refraction at the nematic-isotropic transition in the E7 thermotropic liquid crystal
Fecha
2012Registro en:
EUROPEAN PHYSICAL JOURNAL E, NEW YORK, v. 35, n. 1, supl. 1, Part 3, pp. 546-552, JAN, 2012
1292-8941
10.1140/epje/i2012-12004-3
Autor
Lenart, V. M.
Gomez, S. L.
Bechtold, I. H.
Figueiredo Neto, Antonio Martins
Salinas, Silvio Roberto de Azevedo
Institución
Resumen
We use Z-scan technique to investigate the nonlinear optical response of the thermotropic liquid crystal E7 in the neighborhood of the nematic-isotropic phase transition. The analysis of the data for the nonlinear optical birefringence is compatible with an effective critical exponent of the order parameter, beta = 0.28 +/- 0.03, which is close to the classical value, beta = 0.25, for a tricritical point. The nonlinear optical absorption in the nematic range depends on the geometrical configuration of the nematic director with respect to the polarization beam, and vanishes in the isotropic phase.