Nonlinear Optics of Liquid Crystals

Working group

This research line concerns the investigation of nonlinear optical effects in liquid crystalline materials including also hybrid composite structures. The group is well known for pioneering work on this subject and for having discovered the highest nonlinearity ever measured in nematic liquid crystals doped by Methyl-Red denominated “Colossal Optical Nonlinearity”. In this way became possible to observe nonlinear optical effect with low power laser sources (microwatt). The present activity on this subject concerns the investigation of novel liquid crystal materials and novel hybrid structure in view of possible applications for smart devices based on all-optical control. The new materials include bent-core mesogens, DNA based lyotropic liquid crystals, heliconal cholesterics. The investigation on hybrid structures is presently focused on liquid crystal cells based on Lithium Niobate substrates; light-induced reorientation mediated by the photovoltaic effect is investigated.

Applications of the present research are foreseen in development of smart optical biosensors and environment security.

Several scientific collaborations are active on these subjects in particular with: Kent State University (USA), Taras Shevchenko National University of Kiev (Ukraine), University of Padova and University of Milano (Italy).