Entangled States and the Gravitational Quantum Well

TL;DR

This paper investigates how Earth's gravity affects quantum entanglement in a bipartite system, using phase-space methods and PPT criteria, with implications for quantum communication across gravitational potentials.

Contribution

It provides a phase-space analysis of gravitational effects on entanglement and extends PPT criteria to non-Gaussian states in this context.

Findings

Gravity influences entanglement in bipartite systems.

Phase-space description via Wigner function is effective.

Gravity impacts quantum communication protocols.

Abstract

We study the continuous variable entanglement of a system of two particles under the influence of Earth's gravitational field. We determine a phase-space description of this bipartite system by calculating its Wigner function and verify its entanglement by applying a generalization of the PPT criterion for non-Gaussian states. We also examine the influence of gravity on an idealized entanglement protocol to be shared between stations at different potentials based on the correlation of states of the gravitational quantum well.