Fast and ultrafast all-optical control of light in nematic and smectic-A liquid crystals

Abstract

© 2016 SPIE. We review recent experiments on the fast and ultrafast all-optical control of light in bulk nematic and smectic-A liquid crystals. Ultrafast optical control at sub-picosecond time scalecan be achieved via the optical Kerr response of a nematic liquid crystal. We show that the refractive index changes are of the order of 10 -4 in 5CB nematic liquid crystal and can be optically induced by applying 100 fs pulses of 4 mJ/cm 2 fluence. We discuss stimulated emission depletion of fluorescence in a smectic-A liquid crystal and demonstrate nanosecond light control of fluorescent pulse shaping. Both methods could be applied to control light by light in future photonic devices based on liquid crystals.