Giant emitter magnetometer

Leveraging the sensitive dependence of a giant atom's radiation rate on its frequency [A. F. Kockum, $et~al$., Phys. Rev. A 90, 013837 (2014)], we propose an effective magnetometer model based on single giant emitter. In this model, the emitter's frequency is proportional to the applied bias magnetic field. The self-interference effect causes the slope of the dissipation spectrum to vary linearly with the number of emitter-coupling points. The giant emitter magnetometer achieves a sensitivity as high as $10^{-8}-10^{-9}\,{\rm T/\sqrt{Hz}}$, demonstrating the significant advantages of the self-interference effect compared to small emitters. We hope our proposal will expand the applications of giant emitters in precision measurement and magnetometry.