Abstract
Stark effect investigations in the 6, 7 and 8 2D3/2,5/2 levels of 85Rb and the 8, 9 and 10 2D3/2,5/2 levels of 133Cs were performed with the level crossing technique. The levels were populated in a two-step excitation process, involving a CW tunable dye laser. The tensor polarizability of all states was measured and a good agreement with theoretical values, obtained with the Coulomb approximation, is found. Furthermore, the signs of the dipole interaction constants, determined to absolute value in earlier experiments, could be inferred. The sign was found to be positive for the 2D3/2 states and negative for the 2D5/2 states, indicating strong polarization effects in the magnetic hyperfine interaction.