Quantum Gravitational Sensor for Space Debris

TL;DR

This paper models a quantum matter-wave interferometer for detecting space debris by measuring gravity gradients, analyzing its sensitivity, and estimating the minimum detectable mass of objects near satellites.

Contribution

It introduces a three-dimensional model for gravity gradient signals and evaluates the sensitivity of a Stern-Gerlach based matter-wave interferometer for space debris detection.

Findings

Sensitivity analysis shows potential to detect small mass objects near satellites.

Quantitative estimates of minimum detectable mass based on object distance and velocity.

Application of the model to space debris detection scenarios.

Abstract

Matter-wave interferometers have fundamental applications for gravity experiments such as testing the equivalence principle and the quantum nature of gravity. In addition, matter-wave interferometers can be used as quantum sensors to measure the local gravitational acceleration caused by external massive moving objects, thus lending itself for technological applications. In this paper, we will establish a three dimensional model to describe the gravity gradient signal from an external moving object, and theoretically investigate the achievable sensitivities using the matter-wave interferometer based on the Stern-Gerlach set-up. As an application we will consider the Mesoscopic Interference for Metric and Curvature (MIMAC) and Gravitational wave detection scheme [New J. Phys. 22, 083012 (2020)] and quantify its sensitivity to gravity gradients using frequency-space analysis. We will consider objects near Earth-based experiments and space debris in proximity of satellites and estimate the minimum detectable mass of the object as a function of their distance, velocity, and orientation.