OPTICALLY INDUCED HYDRODYNAMIC REORIENTATION OF LIQUID-CRYSTALS AND ITS APPLICATIONS FOR INFRARED DETECTION AND INFORMATION-STORAGE

Absorption mediated effects provide the strongest mechanisms of optically induced reorientation of liquid crystals (LC's). The following mechanism of transformation of absorbed light energy into reorientation of LC's is theoretically discussed in the present paper: thermal expansion resulting from absorption induced heating causes inhomogeneous flow of the LC in the capillary which, due to the strong coupling of hydrodynamic and orientational degrees of freedom, leads to LC reorientation. With a plane capillary, this may allow detection of infrared radiation at a microwatt level. With microcapillaries in porous media, this may lead to chaotization of orientation and creation of scattering pixels allowing for high resolution optical information storage matrixes. Estimations done for so called ''filled nematic liquid crystals'' are in good accordance with existing experimental data.