Compact apparatus for an atom-chip gyroscope

Sagnac atom interferometers are a promising technique for high-performance rotation sensing, with potential applications for inertial navigation. The use of trapped atoms for the interferometer avoids the need for long free-fall distances that would be incompatible with a navigation apparatus. We have previously demonstrated a dual Sagnac interferometer using Bose-condensed atoms in a time-orbiting potential trap, with an enclosed area of 8.2mm² and corresponding rotation sensitivity of 6x10^-7 rad/s at shot-noise limited detection. A limiting factor in the development and deployment of atom interferometer gyroscopes is their large size. We report on the design and progress of a compact version of the experiment using a novel type of atom chip for the time-orbiting potential trap. The compact system uses a volume of only fifty liters for all optics, vacuum chamber and magnetic coils, and the chip should allow a factor of ten improvement in operation rate.