Open AccessOptimal densities of alkali metal atoms in an optically pumped K–Rb hybrid atomic magnetometer considering the spatial distribution of spin polarization
Author(s) -
Yosuke Ito,
Sato Daichi,
Kei Kamada,
Tetsuo Kobayashi
Publication year - 2016
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.015391
Subject(s) - rubidium , homogeneity (statistics) , magnetometer , polarization (electrochemistry) , materials science , spin polarization , atomic physics , alkali metal , bloch equations , spatial distribution , optics , potassium , magnetic field , physics , nuclear magnetic resonance , electron , chemistry , statistics , mathematics , quantum mechanics , metallurgy
An optically pumped K-Rb hybrid atomic magnetometer can be a useful tool for biomagnetic measurements due to the high spatial homogeneity of its sensor property inside a cell. However, because the property varies depending on the densities of potassium and rubidium atoms, optimization of the densities is essential. In this study, by using the Bloch equations of K and Rb and considering the spatial distribution of the spin polarization, we confirmed that the calculation results of spin polarization behavior are in good agreement with the experimental data. Using our model, we calculated the spatial distribution of the spin polarization and found that the optimal density of K atoms is 3 × 10 19 m -3 and the optimal density ratio is n K /n Rb ~ 400 to maximize the output signal and enhance spatial homogeneity of the sensor property.