The newly formed ALPHA collaboration has begun work towards building a tunable, cryogenic, plasma haloscope using wire metamaterials. The plasma haloscope is a novel method for the detection of the resonant conversion of axions to photons. Traditional cavity and dielectric haloscopes compensate for the momentum mismatch between the axion and the massless photon by breaking translational invariance. In this case, reaching higher axion masses with sufficient sensitivity is a challenge due to the very small structures needed. Plasma haloscopes instead use a tunable plasma frequency to match the axion mass. The plasma frequency of a wire metamaterial can be tuned to match the axion mass by changing the interwire spacing, allowing for large conversion volumes. This talk will give an overview of the plasma haloscope concept and the ongoing experimental effort of the ALPHA collaboration.
Monday, February 28, 2022 - 14:30
CENPA Conference Room NPL-178