Tunability Dependence of All-Optical Liquid Crystal Delay Line on Laser Polarization and Incidence Angle

—This work experimentally investigates the optical manipulation of trans-cis swaps and, resultantly, their optical/electromagnetic imprints as a driver for realizing the tunable delay lines in the microwave X band (8-12 GHz) regime utilizing the polarization and incident angle dependencies of azo-admixed liquid crystals (LCs). Measurement results confirm that the tuning efficacy of the azo-LCs-based delay line is highly dependent on the polarization of the laser beam concerning the rubbing and filling directions of LCs. The achievable differential phase shift is maximized when the laser light beam is polarized parallel to the rubbed direction and the LCs filling direction.