Barium Titanate and Lithium Niobate Permittivity and Pockels Coefficients from MHz to Sub-THz Frequencies

Abstract

The Pockels effect is essential for controlling optical signals at the highest speeds, particularly for electro-optic modulators in photonic integrated circuits. Lithium niobate (LN) and barium titanate (BTO) are two excellent Pockels materials to this end. Here, we measure the Pockels coefficients and permittivity in LN and BTO over a continuous frequency range from 100 MHz to 330 GHz. These properties are constant across this frequency range in LN but have a significant frequency dependence in BTO. Still, our measurements show that BTO has remarkably large electro-optic properties compared to LN. Furthermore, we show how BTO devices can be designed with a flat electro-optic frequency response despite the Pockels coefficient dispersion. Finally, we expound our method for broadband characterization of these vital electro-optic properties, utilizing specialized integrated electro-optic phase shifters. Altogether, this work empowers the design of high-speed BTO devices and the development of new electro-optic materials.

Main Text: 21 pages, 5 figures. Supplementary Information: 22 pages, 10 figures

References in corpus (4)

• Integrated Photonic Quantum Technologies
• Spatially entangled photon-pairs from lithium niobate nonlocal metasurfaces
• Cryogenic electro-optic interconnect for superconducting devices
• Plasmonic Ferroelectric Modulators

Cited by in corpus (5)

• Engineering high Pockels coefficients in thin-film strontium titanate for cryogenic quantum electro-optic applications
• Colossal Cryogenic Electro-Optic Response Through Metastability in Strained BaTiO${}_3$ Thin Films
• Scattering-Induced Loss in Ferroelectric Photonic Devices
• Integrated Photonic Devices in Thin-Film Barium Titanate: Opportunities and Challenges
• Scalable quantum interference in integrated lithium niobate nanophotonics