NSF-SNSF: Entanglement Theory in Quantum Networks

Quantum technologies have the potential to radically impact science and society in the information age. In particular, quantum networks may eventually enable distributed quantum computing and new forms of quantum sensing. However, a deeper theoretical understanding of quantum networking is needed in order to verify the functionality and guide the development of novel architectures and use-cases for quantum networks.

This project will explore new theoretical tools to study how entangled states can be created, manipulated, certified, and characterized in realistic quantum networks. This project will make a strong connection with current experimental capabilities while developing methods and protocols that are of direct relevance to current and near-term quantum network implementations.

This project is structured along two main research lines. In one direction the research team aims to characterize the structure of multipartite entanglement in networks. The key questions are: which entangled states can be generated in a network?

How can one efficiently certify multipartite entanglement in networks? How can one quantify network entanglement in an operationally meaningful way? In a second direction this team will explore the properties of quantum measurements at each network node.

The fundamental questions they will explore are: what type of local measurements are possible when multiple quantum signals are received at different times and quantum memory is limited? What classes of multipartite entangled states can be generated under constrained entanglement swapping measurements? How do restricted local measurements lead to novel notions of network quantum steering and data hiding?

This research project is poised to initiate new experimental collaborations, such as with researchers at both the PIs home institutions, the University of Geneva and the University of Illinois Urbana-Champaign. The US-Swiss scientific collaboration supported by this project will therefore grow beyond just the two PIs. This collaborative U.S.-Swiss project is supported by the U.S.

National Science Foundation (NSF) and the Swiss National Science Foundation (SNSF), where NSF funds the U.S. investigator and SNSF funds the partners in Switzerland.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.