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arXiv · 2005.00897

Cryogenic microwave-to-optical conversion using a triply-resonant lithium niobate on sapphire transducer

Timothy P. McKenna·Jeremy D. Witmer·Rishi N. Patel·Wentao Jiang·Raphaël Van Laer·Patricio Arrangoiz-Arriola·E. Alex Wollack·Jason F. Herrmann·Amir H. Safavi-Naeini
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Abstract

Quantum networks are likely to have a profound impact on the way we compute and communicate in the future. In order to wire together superconducting quantum processors over kilometer-scale distances, we need transducers that can generate entanglement between the microwave and optical domains with high fidelity. We present an integrated electro-optic transducer that combines low-loss lithium niobate photonics with superconducting microwave resonators on a sapphire substrate. Our triply-resonant device operates in a dilution refrigerator and converts microwave photons to optical photons with an on-chip efficiency of $6.6\times 10^{-6}$ and a conversion bandwidth of 20 MHz. We discuss design trade-offs in this device, including strategies to manage acoustic loss, and outline ways to increase the conversion efficiency in the future.

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Timothy P. McKenna, Jeremy D. Witmer, Rishi N. Patel, Wentao Jiang, Raphaël Van Laer, Patricio Arrangoiz-Arriola, E. Alex Wollack, Jason F. Herrmann, Amir H. Safavi-Naeini. 2020-05-02. Cryogenic microwave-to-optical conversion using a triply-resonant lithium niobate on sapphire transducer. https://arxiv.org/abs/2005.00897

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