Ensemble electron spin coherence of Rb atoms trapped in solid neon.*

Rb atoms trapped in solid neon exhibit red-shifted laser-induced fluorescence and are highly resistant to optical bleaching. In this talk, we explore the additional properties needed for single-atom quantum sensing, focusing on the electron spin coherence lifetimes of Rb atoms implanted in solid Ne. We find that we can greatly enhance the ensemble electron spin coherence using dynamical decoupling techniques, making them highly sensitive ac magnetometers which are promising for applications in single-molecule NMR and nano-MRI. We also study the effects of sample growth conditions and the interactions of Rb atoms with the ²¹Ne spin bath on T₂.