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arXiv · 2304.06562

On the use of dielectric elements in axion searches with microwave resonant cavities

Xiran Bai·Michael J. Jewell·Steve K. Lamoreaux·Reina H. Maruyama·Karl van Bibber
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Abstract

This study explores the primary effects of dielectric materials in a resonant cavity-based search for axion dark matter. While dielectrics prove beneficial in numerous cases, their incorporation may lead to less-than-optimal performance, especially for the lowest TM mode. Additionally, the stronger confinement of the electric field inside the dielectrics can exacerbate mode mixings, in particular for higher-order modes. Case studies have been carried out using a combination of analytical solutions and numerical simulations. The findings indicate dielectric cavities employing the $\text{TM}_{010}$ mode experience a significant reduction in sensitivity when compared to a similar search conducted in a cavity at equivalent frequency using no dielectrics.

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Xiran Bai, Michael J. Jewell, Steve K. Lamoreaux, Reina H. Maruyama, Karl van Bibber. 2023-04-13. On the use of dielectric elements in axion searches with microwave resonant cavities. https://doi.org/10.1088/1748-0221%2F18%2F07%2Fp07017

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