Colossal Nonlinear Optical Effect in Dye-Doped Liquid Crystals

Abstract

In this work, we studied a newly reported class of colossal nonlinear effects observed near the nematic-isotropic temperature transition. We show that the origin of this nonlinearity may be attributed to the onset of critical opalescence. Large diffraction efficiency (23%) and colossal nonlinear refractive index (n₂ ≈ 50 cm²/W) has been measured in randomly oriented thin (1 μm) films of 5CB liquid crystals doped with small quantities of the azo dye methyl red (1%wt).

Keywords:

• critical opalescence
• gratings
• methyl red
• nematic liquid crystals

Acknowledgments

RRG wants to thanks the support of CONACYT through Grant 45950 and Merck-Mexico for its financial support.