Energy transfer between the ^S and ²D states in alkalis: Experiments and theory

Collisional energy transfer (ET) between the ²S and ²D states of alkali atoms is reviewed. Recent experimental results on the ET in homonuclear collisions in Na, K, and Rb vapours upon cw (continuous wave) and pulsed laser excitation, as well as theoretical calculations of the respective cross sections are discussed. The mechanisms of these processes are considered in an attempt to clarify the role of the dipole-dipole interaction.