We report the observation of enhanced nonlinear optical responses of methyl-red-doped blue-phase liquid crystals by application of a DC field. We have observed strong multi-order nonlinear grating diffractions characterized by a nonlinear index coefficient n2 ∼ 0.5 cm2/W using unfocused CW laser power of ∼1 mW and a DC field of a few V/μm. The underlying mechanisms are crystalline lattice and director axis reorientations by torques exerted by the DC field and photo-excited dye molecules.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics