Quantum ballistic experiment on antihydrogen fall

TL;DR

This paper proposes an interferometric method to precisely measure the gravitational mass of antihydrogen by analyzing the time distribution of annihilation events after free fall, utilizing quantum superpositions and resonant transitions.

Contribution

It introduces a novel interferometric approach combining quantum superpositions and magnetic resonance to measure antihydrogen's gravitational mass with high precision.

Findings

The method can accurately relate time distribution to initial momentum states.

Resonant magnetic transitions enable creation of gravitational quantum state superpositions.

Estimated measurement accuracy for antihydrogen gravitational mass is promising.

Abstract

We study an interferometric approach to measure gravitational mass of antihydrogen. The method consists of preparing a coherent superposition of antihydrogen quantum state localized near a material surface in the gravitational field of the Earth, and then observing the time distribution of annihilation events followed after the free fall of an initially prepared superposition from a given height to the detector plate. We show that a corresponding time distribution is related to the momentum distribution in the initial state that allows its precise measurement. This approach is combined with a method of production of a coherent superposition of gravitational states by inducing a resonant transition using oscillating gradient magnetic field. We estimate an accuracy of measuring the gravitational mass of antihydrogen atom which could be deduced from such a measurement.