$T^{-3}$-shift in a short-baseline atomic interferometer-gravimeter

TL;DR

This paper reports the first experimental detection of a lineshape asymmetry-caused shift in a short-baseline atomic gravimeter, which scales with the inverse cube of the free evolution time and affects high-precision gravity measurements.

Contribution

It provides the first experimental observation and analysis of the $T^{-3}$-scaling LACS in short-baseline atomic gravimeters, confirming previous theoretical predictions.

Findings

LACS scales as $T^{-3}$ and causes systematic errors in g measurements.

The experimental results agree with prior theoretical models.

LACS can induce errors of 0.1-1 mGal in gravity measurements.

Abstract

This paper presents the first experimental observation and investigation of a lineshape-asymmetry-caused shift (LACS) in a short-baseline atomic interferometer-gravimeter. It is shown that this shift scales inversely with the cube of the free evolution time, $\propto T^{-3}$, and can lead to a noticeable systematic error in the measured value of the gravitational acceleration g at the level of 0.1-1 mGal ($T\approx$ milliseconds). The obtained results are in good agreement with our previous theoretical studies and highlight the importance of accounting for LACS in high-precision absolute measurements of g in compact atomic gravimeters.