Precision Measurement of the Excited State Landé g-factor and Diamagnetic Shift of the Cesium D2 Line

Stærkind, Hans; Jensen, Kasper; Müller, Jörg H.; Boer, Vincent O.; Petersen, Esben T.; Polzik, Eugene S.

Abstract

Transitions between the extreme angular-momentum states of alkali D lines hold the potential for enabling accurate high-field optical magnetometry because of their very simple magnetic field dependence described only by a linear and a quadratic term, characterized by the two coefficients γ1 and γ2. Here, we present very accurate measurements of these coefficients, for the cesium D2 line, thereby overcoming a major obstacle for the realization of this future technology. By means of saturated absorption spectroscopy on a cesium gas, in 3 T and 7 T magnetic fields, we measure the linear magnetic frequency shift of the transition to be γ1=13.994 301(11) GHz/T. This measurement corresponds to an optical magnetic field determination of better than 1 ppm accuracy. From this value, we can calculate the fine-structure Landé g-factor gJ(62P3/2)=1.334 087 49(52). This result is consistent with the previous best measurement, and it improves the accuracy by more than 2 orders of magnitude. We also measure, for the first time, the quadratic diamagnetic shift as γ2=0.4644(35) MHz/T2. Our work opens up the field of accurate high-field optical magnetometry using atomic cesium, with possible applications in, e.g., medical MRI, fusion reactors, and particle accelerators. These high-accuracy measurements also allow for testing of advanced atomic structure models, as our results are incompatible with the Russel-Saunders coupling value and the hydrogen-constant-core-model value by 31 and 7 standard deviations, respectively.

Citation

Stærkind, H., Jensen, K., Müller, J. H., Boer, V. O., Petersen, E. T., & Polzik, E. S. (2023). Precision Measurement of the Excited State Landé g-factor and Diamagnetic Shift of the Cesium D2 Line. Physical Review X, 13(2), Article 021036. https://doi.org/10.1103/PhysRevX.13.021036

• Journal Article Type: Article
• Acceptance Date: Feb 24, 2023
• Online Publication Date: Jun 20, 2023
• Publication Date: Apr 1, 2023
• Deposit Date: Jun 26, 2023
• Publicly Available Date: Jun 27, 2023
• Journal: Physical Review X
• Electronic ISSN: 2160-3308
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 13
• Issue: 2
• Article Number: 021036
• DOI: https://doi.org/10.1103/PhysRevX.13.021036
• Keywords: Atomic & molecular processes in external fields; Atomic & molecular structure; Atomic spectra; Magneto-optical spectra; Strong electromagnetic field effects; Strong-field-induced spectra
• Public URL: https://nottingham-repository.worktribe.com/output/22186672
• Publisher URL: https://journals.aps.org/prx/abstract/10.1103/PhysRevX.13.021036