Tune-out wavelengths for helium-like ions in plasma environments

Abstract

We investigate the influence of model plasma environments on the tune-out wavelengths for helium-like ions based on the Debye–Hückel shielding approach to plasma modeling. The dynamic polarizability for the lowest singlet and triplet S-states of the helium-like ions (Z = 3–8) for various screening parameters are calculated using correlated exponential wave functions within the framework of pseudostates summation method. Frequency-dependent polarizability for the 2 3S state; energies for the 1 1S → 2 1P and 2 3S → 2 3P transitions; tune-out wavelengths for the 1 1S and 2 3S states as functions of screening parameter, are reported. For the unscreened cases, our results are in agreement with the available theoretical and experimental predictions.