2024/05/14 by Iman Taghavi, Omid Esmaeeli, Taghavi, Iman +20 · 3 citations
Engineering · Materials Science · #Applied Physics (physics.app-ph) #FOS: Physical sciences #Liquid Crystal Research Advancements #Optical Polarization and Ellipsometry #Optics (physics.optics) #Photonic and Optical Devices
paper · pdf · doi:10.48550/arxiv.2405.08833
openalex publication_date 2024/05/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Organic electro-optic materials have demonstrated promising performance in developing electro-optic phase shifters. Their integration with other silicon photonic processes, nanofabrication complexities, and durability remains to be developed. While the required poling step in electro-optic polymers limits their potential and utilization on a large scale, devices made of paraelectric nematic liquid crystals suffer from slow bandwidth. In ferroelectric nematic liquid crystals, we report an additional GHz-fast phase shift that ultimately allows for significant second-order nonlinear optical coefficients related to the Pockels effect. It avoids poling issues and can pave the way for hybrid silicon-organic systems with CMOS-foundry compatibility. We report DC and AC modulation efficiencies of ≈~0.25 V⋅mm (from liquid crystal orientation) and ≈~25.7 V⋅mm (from Pockels effect), respectively, an on-chip insertion loss of ≈~2.6 dB, and an electro-optic bandwidth of f-6dB>4.18 GHz, employing improved light-matter interaction in a waveguide architecture that calls for only one lithography step.