Iterations of nonlinear entanglement witnesses

2008/06/04 by Tobias Moroder, Otfried Gühne, Norbert Lütkenhaus · 21 citations
Computer Science · Mathematics · Physics and Astronomy · #Algorithm #Applied mathematics #Computer science #Geometry #Iterated function #Limit (mathematics) #Mathematical analysis #Mathematics #Nonlinear system #Orbital Angular Momentum in Optics #Physics #Quadratic equation #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum entanglement #Quantum mechanics #Sequence (biology) #State (computer science) #Term (time) #Witness #quant-ph

paper · pdf · doi:10.1103/physreva.78.032326

published in Physical Review A 78(3) (American Physical Society) · 11 pages, 5 figures

arxiv created 2008/06/04 · openalex publication_date 2008/09/23 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We describe a generic way to improve a given linear entanglement witness by a quadratic, nonlinear term. This method can be iterated, leading to a whole sequence of nonlinear witnesses, which become stronger in each step of the iteration. We show how to optimize this iteration with respect to a given state and prove that in the limit of the iteration the nonlinear witness detects all states that can be detected by the positive map corresponding to the original linear witness.

Citations

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Cited by

• Entanglement witnesses: construction, analysis and classification