Collaborative Research: Optimal Utilization of Quantum Sensing for Axion Dark Matter Searches with ADMX-VERA

The nature of dark matter is one of the biggest mysteries in fundamental physics. Observations from astronomers indicate that a large part of the universe is made up of unknown particles that mainly interact through gravity. Understanding what dark matter really is could have significant effects on fields like cosmology, astrophysics, and particle physics. One promising candidate for dark matter is called the axion. The axion is a theoretical particle that comes from some advanced ideas beyond the Standard Model of particle physics. These ideas aim to solve certain problems in a field known as quantum chromodynamics (QCD). Interestingly, axions might help explain not only the presence of dark matter but also why neutrons do not have a measurable electric dipole moment, which is a puzzling observation in physics. Axions may exist across a broad range of masses, which correspond to specific frequencies. The Axion Dark Matter eXperiment (ADMX) has ruled out key theoretical benchmarks around 1 GHz. Above frequencies of approximately 2 GHz, corresponding to axion masses in the range of several to tens of micro-electronvolts, there exists a large sensitivity gap between current measurements and theoretical benchmarks. This award supports researchers to develop novel “haloscopes” that will improve the search rate of axion dark matter experiments by more than three orders of magnitude over conventional cavities at these higher frequencies. The new haloscopes will be based on geometries that decouple the resonant frequency and the detector volume. Inspired by techniques from radio astronomy and cosmic microwave background (CMB) telescopes, the research team has already achieved promising early results and will continue refining their designs. These developments establish key preparations for future axion searches involving large-volume solenoid magnet systems like those currently utilized for the ADMX project. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.