Anticrossing Spectroscopy

H. J. Beyer, Hans Kleinpoppen

Thomas F. Gallagher

J. B. Marques, Luis Lorenzo Sánchez-Soto, Eusebio Bernabéu

Sacchetti, Andrea

Y -Q Liu, D. Kaiser, Gebhard von Oppen

Anticrossings of the 1s5d and 1s6d 1 Lambda and 3 Lambda Stark sublevels of He I were investigated using radiofrequency spectroscopy. Single and multiple photon transitions were induced and detected after excitation of thermal He atoms by 10-20 keV ion impact. The energy separations of closest approach of four 1s5d and two 1s6d anticrossings were deduced from the resonance signals.

R. C. Stoneman, Thomas F. Gallagher

We report the observation of anticrossing signals arising from the interaction of 300-K blackbody radiation with Rydberg atoms near avoided crossings of Stark levels. The role of the blackbody radiation is roughly analogous to that of the resonance fluorescence in traditional anticrossing spectroscopy. We present preliminary results for avoided crossings of $\mathrm{ns}$ states with $n\ensuremath{-}2$ Stark states in potassium for $n$ in the range 18-21.