Assembling a Ring-Shaped Crystal in a Microfabricated Surface Ion Trap

Abstract

We report on experiments with a microfabricated surface trap designed for confining a chain of ions in a ring. Uniform ion separation over most of the ring is achieved with a rotationally symmetric design and by measuring and suppressing undesired electric fields. After reducing stray fields, the ions are confined primarily by a radio-frequency pseudopotential and their mutual Coulomb repulsion. Approximately 400 Ca-40(+) ions with an average separation of 9 mu m comprise the ion crystal.