English

Microwave cavity searches for low-frequency axion dark matter

High Energy Physics - Phenomenology 2020-07-22 v3 High Energy Physics - Experiment

Abstract

For low-mass (frequency \ll GHz) axions, dark matter detection experiments searching for an axion-photon-photon coupling generally have suppressed sensitivity, if they use a static background magnetic field. This geometric suppression can be alleviated by using a high-frequency oscillating background field. Here, we present a high-level sketch of such an experiment, using superconducting cavities at \sim GHz frequencies. We discuss the physical limits on signal power arising from cavity properties, and point out cavity geometries that could circumvent some of these limitations. We also consider how backgrounds, including vibrational noise and drive signal leakage, might impact sensitivity. While practical microwave field strengths are significantly below attainable static magnetic fields, the lack of geometric suppression, and higher quality factors, may allow superconducting cavity experiments to be competitive in some regimes.

Keywords

Cite

@article{arxiv.1912.11056,
  title  = {Microwave cavity searches for low-frequency axion dark matter},
  author = {Robert Lasenby},
  journal= {arXiv preprint arXiv:1912.11056},
  year   = {2020}
}

Comments

20 pages, 6 figures; v3: updates for clarity, matches version accepted for Phys Rev D