Accurate measurement of the Sagnac effect for matter waves

A rotating interferometer with paths that enclose a physical area exhibits a phase shift proportional to this area and to the rotation rate of the frame. Understanding the origin of this so-called Sagnac effect has played a key role in the establishment of the theory of relativity and has pushed for the development of precision optical interferometers. The fundamental importance of the Sagnac effect motivated the realization of experiments to test its validity for waves beyond optical, but precision measurements remained a challenge. Here, we report the accurate test of the Sagnac effect for matter waves, by using a Cesium atom interferometer featuring a geometrical area of 11 cm(2) and two sensitive axes of measurements. We measure the phase shift induced by Earth's rotation and find agreement with the theoretical prediction at an accuracy level of 25 parts per million. Beyond the importance for fundamental physics, our work opens practical applications in seismology and geodesy.

Automated summary

The Sagnac effect, which causes a phase shift proportional to the physical area enclosed and the rotation rate of the frame in a rotating interferometer, has played a crucial role in the development of the theory of relativity and precision optical interferometers. This study accurately tests the Sagnac effect for matter waves using a Cesium atom interferometer, demonstrating agreement with theoretical predictions at an accuracy level of 25 parts per million. In addition to its significance in fundamental physics, this work also has practical applications in seismology and geodesy.