Chinese Journal of Quantum Electronics

Energy transfer in Rb(5~2D_J,7S)+Rb(5S) collisions

Yifan Shen

Published Jan 1, 2009• 0 citations

Abstract

Rb vapor was irradiated in a glass fluorescence cell with pulses of radiation from a YAG laserpumped OPO laser,populating 5D_j(or 7S) state by two-photon absorption.Energy transfer in Rb (5D_J,7S)+Rb(5S) collision is studied using methods of atomic fluorescence.The resulting fluorescence includes a direct component emitted in the optically excited state decay and a sensitized component arsing. from the collisional populated state.At the different densities of the components,fitting a three-state rate equation model,the cross sectionσ=(3.7±0.9)×10~(-14) cm~2 was obtained for Rb(5D_(5/2))→Rb(5D_(3/2)) transfer.The cross section for excitation transfer out of the 5D_J doublet are(3.1±1.2)×10~(-14) cm~2(for J = 5/2) and(2.0±0.6)×10~(-14) cm~2(for J = 3/2),respectively.The energy transfer cross section for the Rb(5D)→Rb(7S) is small,(1.6±0.4)×10~(-16) cm~2.The 5D_J state is quenched mainly in the reverse energy pooling processes,i.e.Rb(5D_J)+Rb(5S)→Rb(5P)+ Rb(5P).

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