Magneto-Optic Spectroscopy on Neon Using Laser-Induced Forward Scattering

Abstract

The forward-scattered light observed when a single-mode dye laser interacts with the three neon transitions 1 s5( J = 2)-2 ps( J = 2), 1s3( J = 0)-2 p5( J = 1), and 1 s4( J = 1)-2 p7( J = 1) has been investigated as an applied longitudinal magnetic field is varied. The 1 s5 and the 1 s3 states are metastable. This condition allows a comparison of the spectra for the cases 1 s5( J = 2)-2 p8( J = 2) and 1 s3( J = 0)-2 p5( J = 1) in order to discuss whether the complex line shapes obtained for the J = 2 to J = 2 atomic system are due to higher-order coherences or whether they originate from coherences between m = ±1 states. Experimental and calculated line shapes are presented. The calculations have been performed with the use of a semiclassical model for the light/matter interaction. A J = 0 to J = 1 (or a J = 1 to J = 1) model reproduces the overall shapes of the recorded spectra for all three transitions. The results show that, even when laser beam spatial effects and the sample isotopic effects are taken into account, interpretations of forward-scattering spectra in order to determine atomic parameters can reliably be done for simple J = 0 to J = 1 systems only.