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Bidirectional Millimeter-Wave–Optical Transduction in a Triply Resonant Cavity Electro-Optic System

Shuhang Zheng, Junyin Zhang, Jiachen Cai, Connor Denney, Zihan Li, Yichi Zhang, Xin Ou, Gabriel Santamaría-Botello, Tobias Jan Kippenberg

Published Jan 1, 2026• 0 citations
Publisher

Abstract

We demonstrate bidirectional millimeter-wave–optical transduction in a triply resonant cavity electro-optic system on thin-film lithium tantalate, showing single-photon coupling rate of g 0 = 2 π × 3.11 kHz at 59.33 GHz, transduction efficiency of 2.5%, and resolved room-temperature Johnson noise.
DOI
10.1364/cleo_si.2026.sm1c.7

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Abstract Emerging communications and computing technologies will rely ever-more on expanding the useful radio frequency spectrum into the millimeter-wave and terahertz frequency range. Both classical and quantum applications would benefit from advancing integration and incorporation of millimeter-wave and electro-optic technologies into common devices, such as modulators. Here we demonstrate an integrated triply-resonant, superconducting electro-optic transducer. Our design incorporates an on-chip 107 GHz niobium titanium nitride superconducting resonator, modulating a thin-film lithium niobate optical racetrack resonator operating at telecom wavelengths. We observe a maximum photon transduction efficiency of η OE ≈ 0.82 × 10 −6 and an average single-photon electro-optic interaction rate of g 0 /2 π ≈ 0.7 kHz. We also present a study and analysis of the challenges associated with the design of integrated millimeter-wave resonators and propose possible solutions to these challenges. Our work paves the way for further advancements in resonant electro-optic technologies operating at millimeter-wave frequencies.
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