Optically induced extraordinarily large negative orientational nonlinearity in dye-doped liquid crystal

Laser induced large negative reorientational nonlinearities are observed in dye-doped liquid crystal. The effect is attributed to intermolecular torque exerted by the photoexcited dye molecules, which causes the liquid crystal axis to realign in a direction orthogonal to the optical electric field. Optical nonlinearity as large as 10/sup -2/ cm/sup 2//W in a 37- mu m-thick sample has been observed. In some highly absorptive dyed liquid crystal, the orientational effect can be much larger than the thermal effect.<
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