2015/12/31 by Brian T. Kirby, Siddhartha Santra, Vladimir S. Malinovsky +1 · 49 citations
Computer Science · Mathematics · Physics and Astronomy · #Algorithm #Cluster state #Combinatorics #Computer science #Concurrence #Mathematics #Multipartite entanglement #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum entanglement #Quantum mechanics #Qubit #Squashed entanglement #State (computer science) #Statistical physics #Topology (electrical circuits) #W state #quant-ph
paper · pdf · doi:10.1103/physreva.94.012336
published in Physical Review A 94(1) (American Physical Society)
openalex publication_date 2016/07/20 · arxiv created 2016/07/25 · arxiv updated 2016/07/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We consider entanglement swapping, a key component of quantum network operations and entanglement distribution. Pure entangled states, which are the desired input to the swapping protocol, are typically mixed by environmental interactions, causing a reduction in their degree of entanglement. Thus an understanding of entanglement swapping with partially mixed states is of importance. Here we present a general analytical solution for entanglement swapping of arbitrary two-qubit states. Our result provides a comprehensive method for analyzing entanglement swapping in quantum networks. First, we show that the concurrence of a partially mixed state is conserved when this state is swapped with a Bell state. Then, we find upper and lower bounds on the concurrence of the state resulting from entanglement swapping for various classes of input states. Finally, we determine a general relationship between the ranks of the initial states and the rank of the final state after swapping.