2003/07/05 by Ulrike Herzog
Computer Science · Mathematics · Physics and Astronomy · #Algorithm #Cluster state #Mathematics #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum error correction #Quantum mechanics #Quantum state #Qubit #State (computer science) #Statistical physics #quant-ph
paper · pdf · doi:10.1088/1464-4266/6/3/005
6 pages, contribution to the 10th CEWQO, submitted to J. Opt. B
arxiv created 2003/07/05 · openalex publication_date 2004/03/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The problem of discriminating with minimum error between two mixed quantum states is reviewed, with emphasis on the detection operators necessary for performing the measurement. An analytical result is derived for the minimum probability of errors in deciding whether the state of a quantum system is either a given pure state or a uniform statistical mixture of any number of mutually orthogonal states. The result is applied to two-qubit states, and the minimum error probabilities achievable by collective and local measurements on the qubits are compared.