Modulation of defect modes intensity by controlled light scattering in photonic crystal with liquid crystal domain structure

- The setup to measure spectra of the PC with spatially extended nematic is ensured.
- The electric-field-induced decay of photonic crystal defect modes is studied.
- The modulation technique of the PC spectra based on the nematic electroconvection.

A method to modulate the defect modes intensity in a multilayer photonic crystal with a nematic liquid crystal layer arranged midmost has been proposed. The various electrohydrodynamic domain structures (Williams domains, oblique rolls and grid pattern) were formed in the nematic layer under the action of ac electric field. The domains cause a polarization-sensitive light scattering which leads to an anisotropic reduction of the defect modes intensity. Thus by varying the applied voltage, we can tune gradually the transmittance spectrum of photonic crystal. In addition, the spectrum strongly depends on the light polarization direction above threshold voltage.