Study of low energy Ytterbium atom-ion charge transfer collisions using a surface-electrode trap

Abstract

We demonstrate a new isotope-selective system to measure low energy charge transfer collisions between ytterbium ions and atoms in the range of collisional energy from 2.2x 10-5 eV to 4.3x 10-3 eV, corresponding to effective temperature from 250 mK to 50 K. The charge transfer collisions are observed by spatially overlapping the 172yb+ ions in the surface-electrode trap and 174Yb atoms in the magneto-optical trap, and measuring ion loss. We confirm that, in the Langevin regime, the charge transfer collisional rate is independent of the collisional energy. The measured Langevin cross section is consistent with a theoretical value for the ytterbium atomic polarizability of 143 a.u., as calculated by Zhang and Dalgarno [1].