Nonlinear optical phenomena in fullerene-doped liquid crystal films and fibers

In this presentation, we shall describe the mechanisms and dynamics of two newly observed phenomena in fullerene C₆₀ doped liquid crystal, namely, holographic grating formation in thin film structures and nonlinear pulsed propagation and optical limiting in isotropic liquid crystal cored fibers and fiber arrays. The unusually large photorefractive like nonlinearity of C₆₀ doped nematic film allows us to write permanent holographic gratings which can be electronically modulated. In fullerene-doped liquid crystalline cored fibers, we have observed greatly enhanced nonlinear optical transmission and propagation effects caused by nonlinear scattering, defocusing, increasing absorption and possibly other nonlinear processes. The resulting lower threshold and reduced interaction-length requirement enable one to design practical liquid crystal fiber arrays that could function as imaging faceplate as well as sensor protection devices.