TY - JOUR

T1 - Precision Measurement of the Excited State Landé g-factor and Diamagnetic Shift of the Cesium D2 Line

AU - Stærkind, Hans

AU - Jensen, Kasper

AU - Müller, Jörg Helge

AU - Boer, Vincent Oltman

AU - Petersen, Esben Thade

AU - Polzik, Eugene Simon

PY - 2023/6/20

Y1 - 2023/6/20

N2 - 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.

AB - 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.

UR - http://www.scopus.com/inward/record.url?scp=85164235056&partnerID=8YFLogxK

U2 - 10.1103/PhysRevX.13.021036

DO - 10.1103/PhysRevX.13.021036

M3 - Journal article

SN - 2160-3308

VL - 13

SP - 1

EP - 20

JO - Physical Review X

JF - Physical Review X

IS - 2

M1 - 021036

ER -