T 3 -interferometer for atoms

Abstract

The quantum mechanical propagator of a massive particle in a linear gravitational potential derived already in 1927 by Kennard [2, 3] contains a phase that scales with the third power of the time T during which the particle experiences the corresponding force. Since in conventional atom interferometers the internal atomic states are all exposed to the same acceleration a, this T 3 -phase cancels out and the interferometer phase scales as T 2 . In contrast, by applying an external magnetic field we prepare two different accelerations a 1 and a 2 for two internal states of the atom, which translate themselves into two different cubic phases and the resulting interferometer phase scales as T 3 . We present the theoretical background for, and summarize our progress towards experimentally realizing such a novel atom interferometer.