Quantum Metrology Techniques for Axion Dark Matter Detection

Abstract

Quantum metrology techniques can be used to dramatically improve the signal-to-noise ratio in experimental searches for dark matter axion waves. We first briefly review the cavity haloscope technique including quantum-limited measurements in the Glauber coherent state basis. Quantum non-demolition measurements in the Fock basis are then shown to offer much reduced background rates. Finally, we show that by preparing the cavity photon mode in a Fock state, the axion signal can be enhanced by stimulated emission.