# Integrated millimeter-wave cavity electro-optic transduction

## TL;DR

Researchers developed a new device that combines millimeter-wave and optical technologies to improve communication and quantum computing.

## Contribution

The paper introduces an integrated triply-resonant superconducting electro-optic transducer for millimeter-wave frequencies.

## Key findings

- The device achieved a photon transduction efficiency of ηOE ≈ 0.82 × 10−6.
- An average single-photon electro-optic interaction rate of g0/2π ≈ 0.7 kHz was observed.
- Design challenges for millimeter-wave resonators were analyzed with proposed solutions.

## 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 ηOE ≈ 0.82 × 10−6 and an average single-photon electro-optic interaction rate of g0/2π ≈ 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.

The authors report an integrated triply-resonant superconducting electro-optic transducer combining a 107 GHz NbTiN resonator with a thin-film lithium niobate optical racetrack at telecom wavelengths. Achieving ηOE ≈ 0.82 × 10−6 and g0/2π ≈ 0.7 kHz, this work analyzes mm-wave resonator design challenges and proposes strategies for improved quantum transduction.