Axion detection via topological Casimir effect

Abstract

We propose a new table-top experimental configuration for the direct detection of dark matter QCD axions in the traditional open mass window 10 −6 eV ma 10 −2 eV using non-perturbative effects in a system with non-trivial spatial topology. Different from most experimental setups found in literature on direct dark matter axion detection, which relies onθ or ∇θ, we found that our system is in principle sensitive to a static θ ≥ 10 −14 and can also be used to set limit on the fundamental constant θQED which becomes the fundamental observable parameter of the Maxwell system if some conditions are met. Furthermore, the proposed experiments can probe entire open mass window 10 −6 eV ma 10 −2 eV with the same design, which should be contrasted with conventional cavitytype experiments being sensitive to a specific axion mass. Connection with Witten effect when the induced electric charge e ′ is proportional to θ and the magnetic monopole becomes the dyon with non-vanishing e ′ = −e θ 2π is also discussed.

Gravitationally trapped axions on the Earth

“…We mentioned in Sec.I a number of instruments existing, upgraded (or planning to be upgraded), designed (but not build yet), or under consideration that in principle are capable of achieving the precision required to detect gravitationally-trapped axions. Along with the list of instruments presented in Introduction we also want to mention another possible design, advocated in [78], which is based on quantum coherence of the propagating axions, and which may also benefit from the large coherence length (61) mentioned above. Finally, we want to mention the idea advocated in [79][80][81] that the combination of large number of cavities can drastically enhance the axion signal.…”

Cosmological CP -odd axion field as the coherent Berry’s phase of the Universe

“…Last but not least, the discovery of the axion would conclude a long and fascinating journey of searches for this unique and amazing particle conjectured almost 40 years ago, see recent reviews [9][10][11][12][13][14][15][16], and recent proposal [59] on the axion search experiment which is sensitive to the axion amplitude θ itself, in contrast with conventional proposals which are sensitive toθ.…”

Anomalous Casimir effect in axion electrodynamics

“…In Ref. [79] the topological Casimir effect was proposed as a possible probe to detect the background θ angle and the QCD axion. Thereby, a mixing coupling between electric and magnetic fields plays an important role, which is often referred to as magnetoelectric effect in condensed matter physics.…”