Dressed-State Spectroscopy of Proton Spins in Water Beyond the Rotating-Wave Approximation
Abstract
The quantum Rabi model provides the framework for describing a two-level system interacting with a strong oscillating field beyond the rotating-wave approximation. We report the first experimental observation of the resulting dressed states of proton spins in water, realized using a Rabi-type setup with a strong off-resonant magnetic dressing field. The measured resonance spectrum exhibits multiple spin-state transitions involving several dressing-field quanta, including higher-order resonances predicted by the quantum Rabi model. The dressed-state energies show excellent agreement with theoretical expectations, extending dressed-state spectroscopy to proton spins and opening new possibilities for precision spin manipulation in nuclear magnetic resonance and related precision measurements.
Keywords
Cite
@article{arxiv.2603.14878,
title = {Dressed-State Spectroscopy of Proton Spins in Water Beyond the Rotating-Wave Approximation},
author = {Ivo Schulthess and Anastasio Fratangelo and Patrick Hautle and Philipp Heil and Gjon Markaj and Marc Persoz and Ciro Pistillo and Jacob Thorne and Florian M. Piegsa},
journal= {arXiv preprint arXiv:2603.14878},
year = {2026}
}