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arXiv · 2307.08545

Electromagnetically Induced Transparency and Optical Pumping in the Hyperfine Paschen-Back Regime

Roberto Mottola·Gianni Buser·Philipp Treutlein
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Abstract

We report spectroscopy experiments of rubidium vapor in a high magnetic field under conditions of electromagnetically induced transparency (EIT) and optical pumping. The 1.1 T static magnetic field decouples nuclear and electronic spins and shifts each magnetic state via the Zeeman effect, allowing us to resolve individual optical transitions of the D$_2$ line in a Doppler-broadened medium. By varying the control laser power driving one leg of a spectrally isolated $\Lambda$ system we tune the vapor from the EIT regime to conditions of Autler-Townes line splitting. The resulting spectra conform to simple three-level models demonstrating the effective simplification of the energetic structure. Further, we quantify the viability of state preparation via optical pumping on nuclear spin-forbidden transitions. We conclude that the ``cleanliness'' of this system greatly enhances the capabilities of quantum control in hot vapor, offering advantages in a broad variety of quantum applications plagued by spurious light-matter interaction processes, such as atomic quantum memories for light.

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Roberto Mottola, Gianni Buser, Philipp Treutlein. 2023-07-17. Electromagnetically Induced Transparency and Optical Pumping in the Hyperfine Paschen-Back Regime. https://doi.org/10.1103/physreva.108.062820

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