We realize a non-invasive electrometer based on state engineering in a Rydberg hydrogenic manifold. A quantum interference process involving states with very different dipoles measures directly the time correlation of a stochastic electric field, with a 200~ns time resolution and with a 83.2±1.4~mV/m single-atom sensitivity, beyond the Standard Quantum Limit in this context. This quantum-enabled correlation electrometer opens the way to applications in mesoscopic physics, e.g. for the study of individual charge transits in nano-structures.
@article{arxiv.1805.06870,
title = {Quantum-enabled electrometer measures field transients and correlation function},
author = {E. K. Dietsche and A. Larrouy and J. M. Raimond and M. Brune and S. Gleyzes},
journal= {arXiv preprint arXiv:1805.06870},
year = {2018}
}