Toward Scalable High-Frequency Axion Searches with ADMX

As ADMX tunes to higher frequencies, the cavity volume—and thus axion signal power—drops sharply. Run 2A addresses this by combining signals from four smaller cavities, but extending that approach further becomes complex and hard to scale. The VERA (Volume Enhanced Resonant Axions) effort takes a different route, developing cavity geometries that maintain large effective volumes even at high frequencies by leveraging modes that depend only on a single dimension. Unfortunately, coupling the signal out of this cavity via a wire pickup can cause mode localization, trapping the electric field in part of the cavity. In this talk, I will present our approach to overcoming these challenges by employing for the first time a technique ubiquitous in CMB experiments: an array of slot antennas to enable coherent signal readout for the next generation of axion haloscopes.