Entanglement formation in continuous-variable random quantum networks
Abstract
Entanglement is not only important for understanding the fundamental properties of many-body systems, but also the crucial resource enabling quantum advantages in practical information processing tasks. Although previous works on quantum networks focus on discrete-variable systems, light—as the only traveling carrier of quantum information in a network—is bosonic and thus requires a continuous-variable description. We extend the study to continuous-variable quantum networks. By mapping the ensemble-averaged entanglement dynamics on an arbitrary network to a random-walk process on a graph, we are able to exactly solve the entanglement dynamics. We identify squeezing as the source of entanglement generation, which triggers a diffusive spread of entanglement with a "parabolic light cone”. A surprising linear superposition law in the entanglement growth is predicted by the theory and numerically verified, despite the nonlinear nature of the entanglement dynamics. The equilibrium entanglement distribution (Page curves) is exactly solved and has various shapes depending on the average squeezing density and strength.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 16, 2021
- Source ID
- 10.1038/s41534-021-00370-w
Entities
People
- Bingzhi Zhang
- Quntao Zhuang
Organizations
- Army Research Office
- United States Department of Defense
- University of Arizona