Long-range interaction coefficients for ytterbium dimers

We evaluate the electric-dipole and electric-quadrupole static and dynamic polarizabilities for the $6s^{21}{S}_0$, $6s6p{}^3{P}_0^o$, and $6s6p{}^3{P}_1^o$ states and estimate their uncertainties. A first-principles relativistic method is developed for an accurate calculation of the van der Waals coefficients of dimers involving excited-state atoms with strong decay channel to the ground state. This method is used for evaluation of the long-range interaction coefficients of particular experimental interest, including the $C_6$ coefficients for the Yb-Yb ${}^1{S}_0+{}^3{P}_{0,1}^o$ and ${}^3{P}_0^o+{}^3{P}_0^o$ dimers and $C_8$ coefficients for the ${}^1{S}_0+{}^1{S}_0$ and ${}^1{S}_0+{}^3{P}_1^o$ dimers.

Figure 1

Low-lying energy levels of Yb. Other states of the $4f^{13}5d6s^2$ configuration are not shown.