Selective vibrational pumping of a molecular beam by a stimulated Raman process

Abstract

Stimulated Raman process is used to selectively pump a highly excited vibrational state in a molecular beam. Theoretical evaluation shows that continuous lasers with power of less than 1 W can efficiently pump a single rotational-vibrational level of many simple molecules. The characteristics of the selectively pumped molecular beam and operational conditions are discussed theoretically. The experiment on a ${\mathrm{Na}}_2$ beam is found to agree with theoretical predictions. The flux of 4×${10}^7$ ${\mathrm{s}}^{\mathrm{-}1}$ in the v=31, J=5 excited level has been obtained with use of two cw dye lasers with powers of 80 and 300 mW.