Microseconds-Nanoseconds All-Optical Switching of Visible-Near Infrared (0.5 µm-1.55 µm) Lasers with Dye-Doped Nematic Liquid Crystals

摘要

Laser induced disorder is an efficient and very fast mechanism to induce changes in the birefringence of nematic liquid crystals, which in turn enable many nonlinear optical processes. Using a 90-degrees twist alignment nematic liquid crystal doped with suitable dye to impart the required photonic absorption and order parameter modulation, we have demonstrated ultrafast all-optical shuttle operation for lasers spanning the visible to near-infrared spectral region (532Â nm; 488Â nm; 750Â nm; 1060Â nm; 1550Â nm). With increasing intensity, the on-time of the switch decreases from microseconds to the nanoseconds regime, in such a manner that the transmitted light energy/intensity is clamped to below the eye- or sensor-safe levels.