SUB-DOPPLER COOLING OF 3-LEVEL LAMBDA-ATOMS IN SPACE-SHIFTED STANDINGLIGHT WAVES

We present an investigation of an alternative mechanism for sub-Dopple r cooling of atoms, based on coherent population transfer in three-lev el LAMBDA systems. The mechanism considered is that of a LAMBDA atom i nteracting with two standing light waves with a mutual spatial phase s hift phi not-equal 0. The spatial dependence of the level populations of the LAMBDA atom for different values of phi is presented. For phi n ot-equal 0, this clearly demonstrates coherent population transfer in an atom with transverse motion along the space-shifted nodes and antin odes of the two standing waves. We show that this allows translational temperatures well below the Doppler limit T(D) = hgammaBAR/k(B) to be achieved.