Detectable electric current induced by the dark matter axion in a conductor
Abstract
We propose a method of detecting the dark matter axion by using two slabs of a conductor. The flat surfaces are set face to face, parallel to each other. An external magnetic field B parallel to the surfaces is applied. Radiation converted from the axion arises between the two slabs. When we tune the spacing l between the two surfaces such that l = π/m_{a} with axion mass m_{a}, a resonance occurs so that the radiation becomes strong. Furthermore, the electric current flowing on the surface of the slabs is enhanced. We show that the electric current is large enough to be detectable at the resonance. It reaches 0.7 × 10^{9} A $(10^{5}\, \mbox{eV}/m_a)^{1/2} \, (B/5\, \mbox{T}) \, (L/10\, \mbox{cm}) \, (\sigma /3.3\times 10^7 \, \rm eV)$ using 6N copper for the square slabs with side length L and high electrical conductivity σ at temperature T ~ 1 K. The power of the Joule heating is $0.3\times 10^{22} \, \mbox{W} \, (B/5 \, \mbox{T})^2 \, (10^{5} \, \mbox{eV}/m_a)^{1/2} \, (L/10 \, \mbox{cm})^2 \, (\sigma /3.3\times 10^7 \, \rm eV)$. When we amplify the power using an LC circuit with factor Q_{LC}, the signaltonoise ratio is $4.5\times 10^{4} \, (Q_\mathrm{LC}/10^6) \, (B/5 \, \mbox{T})^2 \, (t_\mathrm{obs}/1\, \mathrm{s})^{1/2}\, (10^{5} \, \mbox{eV}/m_a) \, (L/10 \, \mbox{cm})^2 \, (\sigma /3.3\times 10^7 \, \rm eV)$ with an observation time of t_{obs}.
 Publication:

Progress of Theoretical and Experimental Physics
 Pub Date:
 February 2022
 DOI:
 10.1093/ptep/ptab170
 arXiv:
 arXiv:2111.09468
 Bibcode:
 2022PTEP.2022b1B01I
 Keywords:

 B40;
 B71;
 High Energy Physics  Phenomenology
 EPrint:
 7 pages, 1 figure. To be published in PTEP. arXiv admin note: text overlap with arXiv:2107.06514