Effective splitting of a trapped atomic wave packet in the motional ground state

We briefly review the history and current progress in atom interferometry and atom optics. A descriptive summary of various types of interferometers is followed by a simple account of a new type of beamsplitter for trapped atoms, based on the theoretical idea recently published in Physical Review Letters by a group including ourselves. We show that a trapped atomic wave packet in the motional ground state can be coherently split into two paths effectively with two independent translating traps.