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arXiv · 2610.40793

Layered Wire-Grid Haloscope for Millielectronvolt Axions and Dark Photons

Andrea Caputo
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Abstract

We propose MADGRID (Millielectronvolt Axions and Dark photons with layered GRIDs), a few wire grids in front of a mirror, tuned by their spacing, forming an epsilon-near-zero slab that radiates through its face into external optics. Unlike wire-plasma haloscopes, the signal need not cross the lossy medium to reach an antenna, and metal grids replace the disks of dielectric haloscopes. A 1 m$^2$ array in 10 T could probe axion-photon couplings below the CAST bound up to 1.4 meV with kinetic-inductance detectors, and KSVZ couplings over 0.8-3.9 meV with future photon counters. Without a magnet, it could probe dark photon mixings down to $3.4\times10^{-16}$.

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Andrea Caputo. 2026-10-29. Layered Wire-Grid Haloscope for Millielectronvolt Axions and Dark Photons. https://arxiv.org/abs/2610.40793

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