Laser isotope enrichment of lithium by magnetic deflection of a polarized atomic beam

The authors have succeeded in demonstrating laser isotope enrichment via magnetic deflection of a polarized atomic beam. By using a single dye laser with the frequency tuned to the two accidentally close transitions of the natural lithium (2 2 S 1/2 (F=1/2) to 2 2 P 3/2 for 6 Li and 2 2 S 1/2 (F=2) to 2 2 P 1 2/(F=1) for 7 Li), 6 Li and 7 Li atoms in a beam were positively and negatively polarized respectively. The 6 Li enrichment was achieved via magnetic deflection of the polarized beam through a hexapole magnet which focuses the positively polarized 6 Li atoms and defocuses the negatively polarized 7 Li atoms. The dependence of 7 Li polarization on laser intensity was experimentally examined, and the result was in good agreement with that calculated by rate equations. The abundance ratio of 6 Li to 7 Li was enhanced from 1 : 12.5 to about 1 : 3.1.