Blackbody-radiation shift in a 88Sr+ ion optical frequency standard

Abstract

The blackbody radiation (BBR) shift of the 5s - 4d_{5/2} clock transition in 88Sr+ is calculated to be 0.250(9) Hz at room temperature, T=300K, using the relativistic all-order method where all single and double excitations of the Dirac-Fock wave function are included to all orders of perturbation theory. The BBR shift is a major component in the uncertainty budget of the optical frequency standard based on the 88Sr+ trapped ion. The scalar polarizabilities of the 5s and 4d_{5/2} levels, as well as the tensor polarizability of the 4d_{5/2} level, are presented together with the evaluation of their uncertainties. The lifetimes of the 4d_{3/2}, 4d_{5/2}, 5p_{1/2}, and 5p_{3/2} states are calculated and compared with experimental values.