Fringe-locking method for the weak equivalence principle test by simultaneous dual-species atom interferometers

TL;DR

This paper proposes a fringe-locking method for dual-species atom interferometers that enhances the precision of weak equivalence principle tests by reducing vibration noise and allowing unbiased gravity acceleration measurements.

Contribution

The paper introduces a fringe-locking technique that linearizes phase extraction and improves noise rejection in dual-species atom interferometry for WEP testing.

Findings

Enhanced vibration noise rejection in dual-species interferometers.

Unbiased measurement of gravity acceleration differences.

Feasibility of implementing the fringe-locking method in experiments.

Abstract

We theoretically investigate the application of the fringe-locking method (FLM) in the dual-species quantum test of the weak equivalence principle (WEP). With the FLM, the measurement is performed invariably at the midfringe, and the extraction of the phase shift for atom interferometers is linearized. For the simultaneous interferometers, this linearization enables a good common-mode rejection of vibration noise, which is usually the main limit for high precision WEP tests of dual-species kind. We note that this method also allows for an unbiased determination of the gravity accelerations difference, which meanwhile is readily to be implemented.