Abstract:
We introduce and demonstrate a hybrid optically-pumped magnetometer (hOPM) that simultaneously measures one dc field component and one rf field component quadrature with a single atomic spin ensemble. The hOPM achieves sub-pT/√Hz sensitivity for both dc and rf fields, and is limited in sensitivity by spin projection noise at low frequencies and by photon shot noise at high frequencies. We demonstrate with the hOPM a new application of multi-parameter quantum sensing: background-cancelling spread spectrum magnetic communication. We encode a digital message as rf amplitude, spread among sixteen channels from to in a noisy magnetic environment, and observe quantum-noise-limited rf magnetic signal recovery enabled by quantum-noise-limited dc noise cancellation, reaching noise rejection of at and more than at and below. We measure signal fidelity versus signal strength and extrinsic noise in communication of a short text message. The combination of high sensitivity, quantum-noise-limited performance, and real-world application potential makes the hOPM ideally suited for study of high-performance multi-parameter quantum sensing.
Authors: Michał Lipka, Aleksandra Sierant, Charikleia Troullinou, and Morgan Mitchell
Publication location: Physical Review Applied
Date of publication: 26 March 2024
D.O.I: https://doi.org/10.1103/PhysRevApplied.21.034054
How to cite this article: Michał Lipka, Aleksandra Sierant, Charikleia Troullinou, and Morgan Mitchell. Multiparameter quantum sensing and magnetic communication with a hybrid dc and rf optically pumped magnetometer. Physical Review Applied https://doi.org/10.1103/PhysRevApplied.21.034054
