Magnetically Amplified Tunneling of the Third Kind as a Probe of Minicharged Particles

Abstract

We show that magnetic fields significantly enhance a new tunneling mechanism in quantum field theories with photons coupling to fermionic minicharged particles (MCPs). We propose a dedicated laboratory experiment of the light-shining-through-walls type that can explore a parameter regime comparable to and even beyond the best model-independent cosmological bounds. With present-day technology, such an experiment is particularly sensitive to MCPs with masses in and below the meV regime as suggested by new-physics extensions of the standard model.

Magnetically amplified light-shining-through-walls via virtual minicharged particles

“…We now specify the physical parameter regime, where the corresponding expression for the photon-to-photon transition probability is trustworthy. This turns out to be the case, if the following dimensionless ratios involving ǫeB are large [66]: ǫeB m 2 ≫ 1 and…”

Light dark matter candidates in intense laser pulses I: paraphotons and fermionic minicharged particles

“…Meanwhile, the upper limits derived from the outcomes of the cited experimental collaborations remain many orders of magnitude bigger than the astrophysical one. While a new generation of "Light Shining Through a Wall" experiments might overcome this obstacle [46][47][48], there is a real demand for new theoretical efforts toward the search of complementary scenarios where potential improvements in the bounds of parameters of these dark matter candidates can be achieved [49][50][51].…”

Optical Probes of the Quantum Vacuum: The Photon Polarization Tensor in External Fields

“…(5) is well defined. Given that k B, this prescription of the integration contour allows us to perform the propertime integral explicitly 21 for all the components Π p (k) (p = 1, 2, 3) of the photon polarization tensor; see also Refs. 23 and 24.…”

“…On the other hand, for minicharged particles, neither their mass, nor their charge is restricted a priori, which requires knowledge about the full parameter regime, particularly also in the strong-field limit. Particular 11,12 light-shining-through-walls type experiments 13 also require knowledge about the full momentum dependence. Similar considerations apply to inhomogeneous fields, as soon as the scale of temporal or spatial variations of the external field becomes comparable to the scale set by the Compton wavelength of the virtual particles.…”