Circular Atoms Prepared by a New Method of Crossed Electric and Magnetic Fields

Abstract

Circular atoms, i.e., Rydberg atoms with maximum angular momentum, are semiclassical atoms of great interest for Rydberg constant metrology and QED tests. Following a suggestion by Delande and Gay, we have prepared circular atoms by a new method, involving the adiabatic switching of crossed electric and magnetic fields. The method, which is demonstrated for Rydberg states of lithium (principal quantum number $n=20\mathrm{} \mathrm{to} 25$, is applicable over a wide variety of experiment conditions.