# Quantum interference test of the equivalence principle on antihydrogen

## TL;DR

This paper proposes a quantum interference method to significantly enhance the precision of measuring antihydrogen's free fall acceleration, potentially improving accuracy by three orders of magnitude over classical techniques.

## Contribution

It introduces a quantum interference approach for antihydrogen free fall measurement, offering a simpler and more accurate alternative to existing methods.

## Key findings

- Accuracy improved by ~1000 times with quantum interference
- Method uses existing antiatoms without additional transitions
- Monte-Carlo simulation confirms enhanced precision

## Abstract

We propose to use quantum interferences to improve the accuracy of the measurement of the free fall acceleration g of antihydrogen in the GBAR experiment. This method uses most antiatoms prepared in the experiment and it is simple in its principle as interferences between gravitational quantum states are readout without transitions between them. We use a maximum likelihood method for estimating the value of g and assess the accuracy of this estimation by a Monte-Carlo simulation. We find that the accuracy is improved by approximately three orders of magnitude with respect to the classical timing technique planned for the current design of the experiment.