Bell's shadows from satellites

TL;DR

This paper simulates satellite-ground quantum links to identify regions where Bell tests can be successfully performed, aiding the development of satellite-based quantum networks and protocols.

Contribution

It introduces the concept of Bell violation shadows, regions on Earth where Bell tests are feasible with satellite constellations, enhancing quantum network planning.

Findings

Bell violation shadows move with satellite constellations

Regions suitable for Bell tests can be predicted and mapped

Insights aid in designing satellite-mediated quantum protocols

Abstract

Establishing reliable quantum links between a network of satellites and ground stations is a crucial step towards realizing a wide range of satellite-based quantum protocols, including global quantum networks, distributed sensing, quantum key distribution, and quantum clock synchronization. In this article, we envision a network of satellites and ground stations where quantum links are created through the exchange of entangled photon pairs. We simulate the dynamics of a satellite constellation and a set of Bell tests between the constellation and ground stations. We identify the regions on Earth where Bell tests can be successfully conducted with a satellite or a set of them, at a specified level of confidence. These regions move with the constellation and will be referred to as "Bell violation shadows". We demonstrate that these shadows provide valuable insights for the study and evaluation of many satellite-mediated or satellite-assisted quantum protocols.