Polarization Selection Rules for Two-Photon Processes

  • B. R. Marx
  • L. Allen
Conference paper
Part of the Springer Series in Chemical Physics book series (CHEMICAL, volume 6)


We consider two-photon absorption by a sodium atom from two lasers of frequencies υ1 and υ2, where υ1 and υ2add to give the frequency of the two photon transition υfg. It is well-known that the selection rules governing a 2S1/22S1/2 two-photon absorption when both υ1 and υ2 are far from resonance with any intermediate states, {|i>}, are ΔF = ΔmF= 0, [l]. This is true when |υ1 − υgi| is much larger than the fine and hyperfine structure splittings of {| i>} which are ~ 6 Å and ~ 100 MHz respectively for the 3p intermediate states in the sodium 3s-5s transition. Consideration of the angular momenta of the levels involved leads us to expect selection rules ΔF= 0,± 1, ΔmF = 0, + 1 when |υ1 − υgi| is comparable with the fine structure splitting of the intermediate states and ΔF= 0,± 1, ± 2, ΔmF = 0, ± 1, ± 2, when |υ1 − υgi| is comparable with the hyperfine splitting, [2,3,4, 5]. We have experimentally examined the absorption of two photons circularly polarized in the same sense [5]. In the absence of a magnetic field or collisions this corresponds to ΔmF=±2. The previous discussion indicates that we would expect this absorption to drop close to zero when the detuning from the 32P3/2,1/2 intermediate states is greater than the hyperfine splitting of the state involve’d. However, this is not what we find in our experiment.


Intermediate State Wavelength Dependence Hyperfine Splitting Sodium Atom Photon Transition 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. [1]
    B. Cagnac, G. Grynberg, F. Biraben, Jour de Phys. 34 845 (1974)Google Scholar
  2. [2]
    M. A. Yuratich, D.C. Hanna, J. Phys. B. 9 729 (1976)ADSCrossRefGoogle Scholar
  3. [3]
    D. Cotter, D.C. Hanna, J. Phys. B 92165 (1976)ADSCrossRefGoogle Scholar
  4. [4]
    G. Grynberg, F. Biraben, E. Giacobino, B. Cagnac, Jour de Phys. 38 629 (1977)Google Scholar
  5. [5]
    B.R. Marx, L. Allen J. Phys. B. 11 3023 (1978)ADSCrossRefGoogle Scholar
  6. [6]
    B.R. Marx, G. Holloway, L. Allen Opt. Comm. 18 437 (1976)ADSCrossRefGoogle Scholar
  7. [7]
    J.H. Eberly, B.W. Shore, Z. Biafynicka-Birula, I. Biafynicki-Birula Phys. Rev. A 16 c (1977)CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1979

Authors and Affiliations

  • B. R. Marx
    • 1
  • L. Allen
    • 2
  1. 1.School of Molecular SciencesUniversity of SussexUK
  2. 2.School of Mathematical and Physical SciencesUniversity of SussexUK

Personalised recommendations