Princeton University Gravity Group Lunch Seminar

The QCD axion represents a compelling extension to the Standard Model of particle physics, being both a leading dark matter candidate and a potential solution to the Strong CP problem. In this talk, I describe our efforts toward experimental axion searches, focusing in particular on the Princeton Axion Search (PXS), a laboratory-scale probe for QCD axion dark matter in the 0.8–2 ueV (200–500 MHz) mass range. I overview the experimental techniques and hardware design, including a 5 Tesla magnet being developed in collaboration with PPPL, cryogenics, resonant receivers, and low-noise superconducting electronics. Future searches will aim to probe QCD axion dark matter at lower masses, exploiting measurement protocols operating beyond the Standard Quantum Limit (SQL) of amplification. I discuss Dark Matter Radio (DMRadio), a suite of experiments in sub-ueV range with the ultimate goal of probing GUT-scale axions. As part of this collaboration, we are developing superconducting resonators and readout techniques operating beyond the SQL in the kHz–MHz frequency range.