A large-area Sagnac interferometer using atoms in a time-orbiting potential

We describe an implementation of a Sagnac interferometer using a Bose-Einstein condensate confined in a harmonic time-orbiting potential trap. Atoms are manipulated using Bragg laser beams to produce two reciprocal interferometers, providing common-mode rejection of accelerations, trap fluctuations, and most other effects. The Sagnac rotation phase is differential. The orbit of the atoms is nearly circular, with an effective Sagnac area of about 0.5 mm(2).