Nonlinear liquid crystal optical fiber arrays for all-optical switching/limiting

An experiment was carried out to investigate the performance of an optical limiting/protection device which features a liquid crystal fiber array. The fiber core materials, which was made up of isotropic liquid crystal mixture ILC, was doped with a variety of dopant molecules, including an absorbing liquid crystal LC-X and fullerene, to improve its performance. For picosecond laser pulses, the output versus input energy curves for these liquid crystal core materials all exhibit limiting action at rather low threshold, with the clamped output also very low. With optimized dopant concentration and type, other liquid crystals with high two-photon absorption coefficient, much lower threshold and clamped transmission were obtained.