Suppression of Coriolis error in weak equivalence principle test using 85Rb–87Rb dual-species atom interferometer**Project supported by the National Key Research and Development Program of China (Grant No. 2016YFA0302002), the National Natural Science Foundation of China (Grant Nos. 91736311 and 11574354), Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB21010100), and the Youth Innovation Promotion Association of the Chinese Academy of Sciences (Grant No. 2016300).

Abstract

Coriolis effect is an important error source in the weak equivalence principle (WEP) test using atom interferometer. In this paper, the problem of Coriolis error in WEP test is studied theoretically and experimentally. In theoretical simulation, the Coriolis effect is analyzed by establishing an error model. The measurement errors of Eötvös coefficient (η) in WEP test related to experimental parameters, such as horizontal-velocity difference and horizontal-position difference of atomic clouds, horizontal-position difference of detectors, and rotation compensation of Raman laser’s mirror are calculated. In experimental investigation, the position difference between 85Rb and 87Rb atomic clouds is reduced to 0.1 mm by optimizing the experimental parameters, an alternating detection method is used to suppress the error caused by detection position difference, thus the Coriolis error related to the atomic clouds and detectors is reduced to 1.1× 10−9. This Coriolis error is further corrected by compensating the rotation of Raman laser’s mirror, and the total uncertainty of η measurement related to the Coriolis effect is reduced as δη = 4.4 × 10−11.