Work

Class of Bell-diagonal entanglement witnesses in C4⊗C4 : Optimization and the spanning property

Year: 2022

Type: article

Abstract: Two classes of Bell-diagonal indecomposable entanglement witnesses in ${\mathbb{C}}^{4}\ensuremath{\bigotimes}{\mathbb{C}}^{4}$ are considered. Within the first class, we find a generalization of the well-known Choi witness from ${\mathbb{C}}^{3}\ensuremath{\bigotimes}{\mathbb{C}}^{3}$, while the second one contains the reduction map. Interestingly, contrary to the ${\mathbb{C}}^{3}\ensuremath{\bigotimes}{\mathbb{C}}^{3}$ case, the generalized Choi witnesses are no longer optimal. We perform an optimization procedure of finding spanning vectors that eventually gives rise to optimal witnesses. Operators from the second class turn out to be optimal, however, without the spanning property. This analysis sheds light onto the intricate structure of optimal entanglement witnesses.

Source: Physical Review A

DOI: 10.1103/physreva.105.052401

Authors: Anindita Bera, Filip A. Wudarski, Gniewomir Sarbicki, Dariusz Chruściński

Institutions: Nicolaus Copernicus University, Ames Research Center, Universities Space Research Association, Research Institute for Advanced Computer Science, National Aeronautics and Space Administration

Language: Latvian

Topic: Quantum Information and Cryptography

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

Open Access status: green

Funders: National Aeronautics and Space Administration, Narodowe Centrum Nauki

Awards: G5848006774, G6094436989