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. When the laser light beam is polarized parallel to the rubbed direction as well as the LCs filling direction, the achievable differential phase shift is maximized.

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Author Biography

Jinfeng Li, Beijing Institute of Technology

Prof. Jinfeng Li is a microwave engineer, a specialist in novel reconfigurable RF devices, as well as an authority on liquid crystals-based microwave and millimetre-wave technology. He received the Ph.D. degree in liquid crystals-based microwave and millimeter-wave electronics engineering from University of Cambridge. Prof. Li was a recipient of the IET Award, the AP Jarvis Prize, AETiC Highly Cited Article Award 2023, and two Best Paper Awards at the IEEE and IOP conferences, respectively. He was a Cambridge Trust Scholar, Speaker at the 50th & 46th European Microwave Conferences, Emerging Technologist with Barclays UK, Editorial Board member of 3 Science Citation Index journals, TPC and Session Chair of 5 IEEE conferences, including IEEE ISAP (27th International Symposium on Antennas and Propagation), and IEEE 15th International Conference on Microwave and Millimeter Wave Technology (ICMMT 2023). He was elected Senior Member of China Institute of Communications (CIC), Top 1% Reviewer on Publons (Web of Science), Newton Prize (£1m fund) reviewer for the UK National Commission for UNESCO, and grants reviewer for Health and Social Care Delivery Research (HSDR) fund from National Institute for Health Research (NIHR), UK.




How to Cite

J. Li, “Tunability Dependence of All-Optical Liquid Crystal Delay Line on Laser Polarization and Incidence Angle”, Photonics Lett. Pol., vol. 15, no. 4, pp. 51–53, Dec. 2023.