Magnetically Induced Atomic Transitions of the Potassium D2 Line

Abstract

Magnetically induced (MI) transitions of the D₂ line of ³⁹K atom in an external magnetic field of 10–600 G have been experimentally and theoretically investigated for the first time using circularly polarized σ⁺ and σ⁻ radiations. According to the selection rules, the transitions between the sublevels of the ground and excited levels of a hyperfine structure with F_e – F_g = ΔF = ±2 are forbidden in the zero magnetic field, whereas their probabilities increase radically in a magnetic field. For the F_g = 1 → F_e = 3 (ΔF = +2) and F_g = 2 → F_e = 0 MI transitions, the highest probabilities are achieved using the σ⁺ and σ^– radiations, respectively. The atomic transitions have been spectrally resolved using selective reflection of laser radiation from a nanocell filled with potassium atomic vapor, which makes it possible to investigate the behavior of the MI transitions. The experimental and theoretical data are shown to be in good agreement.