Search for Axion-induced Magnetic Field with Optical Quantum Sensors

We recently proposed a high-precision search for oscillating magnetic field induced by axion dark matter in an external static magnetic field using optical quantum sensors (OQSs) [1]. An OQS based on alkali-metal atoms and lasers is currently the most sensitive cryogen-free magnetic-field sensor. Owing to high sensitivity and operation in a broad frequency range, the OQS can be employed in our axion dark matter search with an inductor-capacitor (LC) circuit at kHz and MHz frequencies. In this talk, we present our OQS-based detection concept in detail and investigate the detection sensitivity to ultralight axion dark matter. We have performed a preliminary experiment with a large-bore strong magnet and a prototype axion detector consisting of a room-temperature LC circuit and a fT-noise OQS unit. We describe the prototype experiment and its projected sensitivity to axions.

[1] Y. J. Kim, L. Duffy, I. Savukov, and P.-H. Chu, “Sensitivity of ultralight axion dark matter search with optical quantum sensors,” Physical Review D 108, 052007 (2023).