2007/06/30 by Otfried Gühne, Chao-Yang Lu, Chao‐Yang Lu +2 · 1 citation
Computer Science · Physics and Astronomy · #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #cond-mat.other #quant-ph
paper · pdf · doi:10.1103/physreva.76.030305
published as Phys. Rev. A 76, 030305 (2007) · 5 pages, no figures, v3: final version, to appear as a Rapid Communication in PRA
arxiv created 2007/09/13 · openalex publication_date 2007/09/18 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The determination of the state fidelity and the detection of entanglement are fundamental problems in quantum information experiments. We investigate how these goals can be achieved with a minimal effort. We show that the fidelity of Greenberger-Horne-Zeilinger and W states can be determined with an effort increasing only linearly with the number of qubits. We also present simple and robust methods for other states, such as cluster states and states in decoherence-free subspaces.