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arXiv · 2405.08833

GHz-rate optical phase shift in light matter interaction-engineered, silicon-ferroelectric nematic liquid crystals

Iman Taghavi·Omid Esmaeeli·Sheri Jahan Chowdhury·Kashif Awan·Mustafa Hammood·Matthew Mitchell·Donald Witt·Cory Pecinovsky·Jason Sickler·Jeff Young·Nicolas A. F. Jaeger·Sudip Shekhar·Lukas Chrostowski
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Abstract

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 $\approx$~0.25 V$\cdot$mm (from liquid crystal orientation) and $\approx$~25.7 V$\cdot$mm (from Pockels effect), respectively, an on-chip insertion loss of $\approx$~2.6 dB, and an electro-optic bandwidth of $f_\text{-6dB}$>4.18 GHz, employing improved light-matter interaction in a waveguide architecture that calls for only one lithography step.

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Iman Taghavi, Omid Esmaeeli, Sheri Jahan Chowdhury, Kashif Awan, Mustafa Hammood, Matthew Mitchell, Donald Witt, Cory Pecinovsky, Jason Sickler, Jeff Young, Nicolas A. F. Jaeger, Sudip Shekhar, Lukas Chrostowski. 2024-05-14. GHz-rate optical phase shift in light matter interaction-engineered, silicon-ferroelectric nematic liquid crystals. https://arxiv.org/abs/2405.08833

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