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Title: Sub‐Nanosecond Tuning of Microwave Resonators Fabricated on Ruddlesden–Popper Dielectric Thin Films

Voltage‐tunable dielectric materials are widely used for microwave‐frequency signal processing. Among tunable dielectric thin films, (SrTiO3)nSrO Ruddlesden–Popper (RP) superlattices have exceptionally low loss at high frequencies. This paper reports the first realization of resonators, a ubiquitous building block of microwave components, fabricated on RP films, and an analysis of their static and dynamic tuning behavior. The RP film has a ferroelectric‐paraelectric phase transition at ≈200 K, and the tunability is strongest at this temperature. The resonators have approximately 2.5% tuning of the resonance frequency at room temperature and 20% tuning at 200 K, and a tuning time scale of less than a nanosecond, which is limited by the measurement circuit rather than material properties.

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Publication Date:
Journal Name:
Advanced Materials Technologies
Wiley Blackwell (John Wiley & Sons)
Sponsoring Org:
National Science Foundation
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