2010/09/30 by F. A. S. Barbosa, A. S. Coelho, A. J. de Faria +4
Computer Science · Mathematics · Physics and Astronomy · #Bipartite graph #Combinatorics #Computer science #Continuous variable #Gaussian #Lossy compression #Mathematical analysis #Mathematical optimization #Mathematics #Multipartite #Multipartite entanglement #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum discord #Quantum entanglement #Quantum mechanics #Robustness (evolution) #Separable space #Separable state #Squashed entanglement #Statistical physics #Statistics #Theoretical computer science #Topology (electrical circuits) #quant-ph
paper · pdf · doi:10.1103/physreva.84.052330
Phys. Rev. A (in press)
arxiv created 2011/11/17 · openalex publication_date 2011/11/28 · arxiv updated 2013/05/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Entanglement in bipartite continuous-variable systems is investigated in the presence of partial losses such as those introduced by a realistic quantum communication channel, e.g., by propagation in an optical fiber. We find that entanglement can vanish completely for partial losses, in a situation reminiscent of so-called entanglement sudden death. Even states with extreme squeezing may become separable after propagation in lossy channels. Having in mind the potential applications of such entangled light beams to optical communications, we investigate the conditions under which entanglement can survive for all partial losses. Different loss scenarios are examined, and we derive criteria to test the robustness of entangled states. These criteria are necessary and sufficient for Gaussian states. Our study provides a framework to investigate the robustness of continuous-variable entanglement in more complex multipartite systems.