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DOE OSTI · 1890807

Novel frequency tunable systems for superconducting cavities (Abbreviated Report)

Castelli, Alessandro R.·Carosi, G. P.·Chaves, K. R.
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Abstract

Ultra-low loss microwave resonant cavities are the backbone of quantum information science (QIS) and axion/dark matter detection (ADMX), but one of the challenges in developing 3D cavity systems has been finding a tuning mechanism that does not drastically reduce the cavity quality factor (Q) but still provides a large operating bandwidth. To alleviate this limitation, we proposed to fabricate a high-Q, 3D microwave cavity with an integrated hybrid mechanical/electrical tuning scheme to achieve both coarse and rapid fine tuning. We implemented two tuning schemes: one using a shift in kinetic inductance and one utilizing mechanical motion. We found that the kinetic inductance method did not yield any tunability in the cavity mode, but the mechanical adjustment successfully moved the cavity resonance. The quality factors obtained were lower than originally proposed, but there is potential to improve the design on further iterations.

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Castelli, Alessandro R., Carosi, G. P., Chaves, K. R.. 2022-09-29. Novel frequency tunable systems for superconducting cavities (Abbreviated Report). https://doi.org/10.2172/1890807

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