Fock-space perturbed relativistic coupled-cluster theory for electric dipole polarizability of one-valence atomic systems: Application to Al and In

Abstract: We have developed a Fock-space relativistic coupled-cluster theory based method for the calculation of electric dipole polarizability of one-valence atoms and ions. We employ this method to compute the ground-state and spin-orbit coupled excited state electric dipole polarizability of Al and In. To check the quality of many-electron wavefunctions, we also compute the excitation energies of some low-lying states of Al and In. The effects of Breit interaction and QED corrections from the Uehling potential and the self-energy are included to improve the accuracy of $\alpha$ further. Our recommended value of ground-state $\alpha$ for both atoms are in good agreement with the previous theoretical results. From our computations, we find that more than 65\% of contributions come from the dipolar mixing of $3p$($5p$) with $3d$($5d$) and $4s$($6s$)-electrons for Al(In). The largest Breit and QED contributions are found to be 1.3\% and 0.6\%, respectively.