Tune-out and Magic Wavelengths for Helium Atom with Exponential-Cosine-Screened Coulomb Potentials
Y. Qiao Wang, Zishi Jiang, Sabyasachi Kar
Abstract
Abstract We investigate the effects of exponential-cosine-screened Coulomb potentials (ECSCP) on the tune-out and magic wavelengths (TMW) of helium atom using correlated exponential wavefunctions based on the pseudostate summation approach. The first tune-out wavelengths (TWs) for the \(\:{\text{}\text{n}}^{\text{}\text{1}}\text{S\:(}\text{n}\text{}\text{=}\text{}\text{1,}\text{}\text{2,}\text{}\text{3)\:}\)and \(\:{\text{n}\text{}}^{\text{3}}\text{S}\text{\:(}\text{n}\text{}\text{=}\text{}\text{2,}\text{}\text{3}\text{)\:}\)states, and the magic wavelengths (MWs) for the \(\:{\text{2}}^{\text{3}}\text{S}\text{}\text{→}{\text{}\text{3}}^{\text{3}}\text{S}\) transition along with the dynamic dipole polarizabities (DDP) for the \(\:{\text{}\text{n}}^{\text{}\text{1}}\text{S\:(}\text{n}\text{}\text{=}\text{}\text{1,}\text{}\text{2,}\text{}\text{3)\:}\) and \(\:{\text{n}\text{}}^{\text{3}}\text{S}\text{\:(}\text{n}\text{}\text{=}\text{}\text{2,}\text{}\text{3}\text{)\:}\)states of helium atom are reported as functions of screening parameter. Our results in the free-atom cases are in good accord with the available theoretical and experimental data. Moreover, the TMW exhibit interesting features as functions of screening parameters, reflecting the unique characteristics of ECSCP.