2000/07/18 by John Calsamiglia, Norbert Lütkenhaus · 19 citations
Computer Science · Mathematics · Physics and Astronomy · #Algorithm #Bell state #Computer science #Entanglement distillation #Mathematics #Neural Networks and Reservoir Computing #Physics #Quantum #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum entanglement #Quantum mechanics #Qubit #Realization (probability) #Simple (philosophy) #State (computer science) #quant-ph
paper · pdf · doi:10.1007/s003400000484
published as Appl. Phys. B 72, 67-71 (2001) · 6 pages, 2 figs
arxiv created 2000/07/18 · openalex publication_date 2001/01/01 · arxiv updated 2015/06/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In a photonic realization of qubits the implementation of quantum logic is rather difficult due the extremely weak interaction on the few photon level. On the other hand, in these systems interference is available to process the quantum states. We formalize the use of interference by the definition of a simple class of operations which include linear optical elements, auxiliary states and conditional operations. We investigate an important subclass of these tools, namely linear optical elements and auxiliary modes in the vacuum state. For this tools, we are able to extend a previous quantitative result, a no-go theorem for perfect Bell state analyzer on two qubits in polarization entanglement, by a quantitative statement. We show, that within this subclass it is not possible to discriminate unambiguously four equiprobable Bell states with a probability higher than 50 %.