Electric quadrupole moment of the $4d^2{D}_{5/2}$ state in ${}^{88}S{r}^{+}$ and its role in an optical frequency standard

Abstract

The electric quadrupole moment for the $4d^2{D}_{5/2}$ state of ${}^{88}\mathrm{S}{\mathrm{r}}^{+}$, one of the most important candidates for an optical clock, has been calculated using the relativistic coupled-cluster theory. The result of the calculation is presented and the important many-body contributions are highlighted. The calculated electric quadrupole moment is $(2.94\pm 0.07)e{a}_0^2$, where $a_0$ is the Bohr radius and $e$ the electronic charge while the measured value is $(2.6\pm 0.3)e{a}_0^2$. This is so far the most accurate determination of the electric quadrupole moment for the above mentioned state.

Revtex, 4 pages, 2 figures