Cooling of a Λ-type three-level atom in a high-finesse optical cavity
Institute of Theoretical Physics, Lanzhou
University, Lanzhou, 730000, P.R. China
2 Key Laboratory for Magnetism and Magnetic materials of the Ministry of Education, Lanzhou University, Lanzhou, 730000, P.R. China
Revised: 18 June 2010
Published online: 1 October 2010
A theoretical study is carried out for the cavity cooling of a Λ-type three-level atom in a high-finesse optical cavity driven by a weakly field. Analytical expressions for the friction, diffusion coefficients and the equilibrium temperature are obtained by using the Heisenberg equations, then they are calculated numerically and shown graphically as functions of the controlling parameters. For a suitable choice of these parameters, the dynamics of the cavity field interaction with the Λ-type three-level atom introduces a sisyphus cooling mechanism yielding lower temperature than the one of the two-level atom, avoiding the problems induced by spontaneous emission.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2010