Abstract

$^{39}{\rm K}$ atoms have the smallest ground state ($^2{S_{1/2}}$) hyperfine splitting of all the most naturally abundant alkali isotopes and, consequently, the smallest characteristic magnetic field value ${B_0} = {A_{^2{S_{1/2}}}}/{\mu _B} \approx 170\,{\rm G}$, where ${A_{^2{S_{1/2}}}}$ is the ground state’s magnetic dipole interaction constant. In the hyperfine Paschen–Back regime ($B \!\gg\! {B_0}$, where $B$ is the magnitude of the external magnetic field applied on the atoms), only eight Zeeman transitions are visible in the absorption spectrum of the ${D_1}$ line of $\,^{39}{\rm K}$, while the probabilities of the remaining 16 Zeeman transitions tend to zero. In the case of $\,^{39}{\rm K}$, this behavior is reached already at relatively low magnetic field $B \!\gt \!{B_0}$. For each circular polarization (${\sigma ^ -},{\sigma ^ +}$), four spectrally resolved atomic transitions having sub-Doppler widths are recorded using a sub-microsized vapor cell of thickness $L = 120 {-} 390\;{\rm nm} $. We present a method that allows to measure the magnetic field in the range of $0.1 {-} 10\;{\rm kG} $ with micrometer spatial resolution, which is relevant in particular for the determination of magnetic fields with large gradients (up to 3 G/µm). The theoretical model describes well the experimental results.

© 2022 Optica Publishing Group

Decoupling of hyperfine structure of Cs D₁ line in strong magnetic field studied by selective reflection from a nanocell

Armen Sargsyan, Emmanuel Klinger, Grant Hakhumyan, Ara Tonoyan, Aram Papoyan, Claude Leroy, and David Sarkisyan
J. Opt. Soc. Am. B 34(4) 776-784 (2017)

Vector magnetometer based on the effect of coherent population trapping

V. Andryushkov, D. Radnatarov, and S. Kobtsev
Appl. Opt. 61(13) 3604-3608 (2022)

Proof of the feasibility of a nanocell-based wide-range optical magnetometer

Emmanuel Klinger, Hrayr Azizbekyan, Armen Sargsyan, Claude Leroy, David Sarkisyan, and Aram Papoyan
Appl. Opt. 59(8) 2231-2237 (2020)

Hyperfine Paschen–Back regime in alkali metal atoms: consistency of two theoretical considerations and experiment

A. Sargsyan, G. Hakhumyan, C. Leroy, Y. Pashayan-Leroy, A. Papoyan, D. Sarkisyan, and M. Auzinsh
J. Opt. Soc. Am. B 31(5) 1046-1053 (2014)

Fluorescence of rubidium in a submicrometer vapor cell: spectral resolution of atomic transitions between Zeeman sublevels in a moderate magnetic field

D. Sarkisyan, A. Papoyan, T. Varzhapetyan, K. Blushs, and M. Auzinsh
J. Opt. Soc. Am. B 22(1) 88-95 (2005)