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arXiv · 2302.12916

Millikelvin measurements of permittivity and loss tangent of lithium niobate

Silvia Zorzetti·Changqing Wang·Ivan Gonin·Sergey Kazakov·Timergali Khabiboulline·Alexander Romanenko·Vyacheslav P Yakovlev·Anna Grassellino
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Abstract

Lithium Niobate is an electro-optic material with many applications in microwave signal processing, communication, quantum sensing, and quantum computing. In this letter, we present findings on evaluating the complex electromagnetic permittivity of lithium niobate at millikelvin temperatures. Measurements are carried out using a resonant-type method with a superconducting radio-frequency (SRF) cavity operating at 7 GHz and designed to characterize anisotropic dielectrics. The relative permittivity tensor and loss tangent are measured at 50 mK with unprecedented accuracy.

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Silvia Zorzetti, Changqing Wang, Ivan Gonin, Sergey Kazakov, Timergali Khabiboulline, Alexander Romanenko, Vyacheslav P Yakovlev, Anna Grassellino. 2023-02-24. Millikelvin measurements of permittivity and loss tangent of lithium niobate. https://doi.org/10.1103/physrevb.107.l220302

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