Giant modification of atomic transition probabilities induced by a magnetic field: forbidden transitions become predominant
Armen D. Sargsyan, A. Tonoyan, G. Hakhumyan +3 more
The magnetic field-induced giant modification of probabilities for seven components of 6S 1/2 , F g = 3 → 6P 3/2 , F e = 5 transition of the Cs D 2 line, forbidden by selection rules, is observed experimentally for the first time. For the case of excitation with circularly polarized laser radiation, the probability of a F g = 3, m F = −3 → F e = 5, m F = −2 transition becomes the largest of 25 transitions of the F g = 3 → F e = 2,3,4,5 group in a wide-range magnetic field of 200–3200 G. Moreover, the modification is the largest among D 2 lines of alkali metals. A half-wave-thick cell (the length along the beam propagation axis L = 426 nm) filled with Cs has been used in order to achieve sub-Doppler resolution, which allows the large number of atomic transitions that appear in the absorption spectrum to be separated when an external magnetic field is applied. For B > 3000 G the group of seven transitions F g = 3 → F e = 5 is completely resolved and is located at the high frequency level of F g = 3 → F e = 2,3,4 transitions. The applied theoretical model describes very well the experimental curves.
arXiv:1401.4587•Laser Physics Letters•Apr 4, 2014•48 citations