Combined effect of plasma screening and electric field on the He atom

Abstract

The combined effect of plasma screening and electric field on the structural properties of atoms/ions is investigated with the help of the relativistic computational method. Two concepts, the ion-sphere model potential and the electric field perturbation operator, which are crucial to perform the current investigation, are introduced to solve the Dirac–Fock equations based on the self-consistent field theory. The developed algorithm is applied to calculation of the plasma-embedded He atom in the case of the field strength 0 ≤F≤ 0.1 a.u. The influences of plasma screening and applied electric field strength, separately and combined, on the energies and radiative transition properties are analyzed in detail. Our results reveal that adding shielding effect destabilizes the atomic system (reduces the energy eigenvalues), and the applied electric field counteracts this effect, thereby increasing the stability of the atomic system. On the whole, the effect of electric field on the electronic structures and spectral properties of the guest atom is a deflection shielding effect, implying that the latter effect is stronger. The present results are in good agreement with the values from the previous literature.