Early Career Scientist Seminar: Barkotel Zemenu, Stanford

High-Frequency Axion Searches with ADMX-VERA

Searching for high-frequency dark matter axions usually requires shrinking detectors, which kills signal power. ADMX-VERA, based at SLAC, solves this by using a novel "thin-shell" design that keeps detector volumes large and signals strong. This talk discusses the prototypes used to validate this design and the readout challenges facing us at these higher frequencies.

Abstract: As the search for dark matter axions moves to higher frequencies, traditional cavity-based detectors must shrink in size, severely reducing the signal power collected from axion-converted photons. While combining multiple cavities can compensate for this loss, scaling such systems introduces significant complexity. To bypass these limitations, the ADMX-VERA (Volume Enhanced Resonators for Axions) collaboration explores alternative geometries that maintain large effective volumes at high frequencies by leveraging modes dependent on only a single dimension. In this talk, I will introduce the "thin-shell" concept motivating this R&D program, present prototype results validating the design, and address a critical challenge associated with coupling to these spatially distributed modes. I will conclude by discussing how we overcome this readout challenge by adapting a technique ubiquitous in cosmic microwave background (CMB) experiments but novel to axion haloscopes.