2006/09/30 by Gui-Fang Dang, Heng Fan
Computer Science · Physics and Astronomy · #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #quant-ph
paper · pdf · doi:10.1103/physreva.76.022323
published as Phys. Rev. A 76, 022323 (2007) · 10 pages, published version
openalex publication_date 2007/08/22 · arxiv created 2007/11/22 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The N to M (M\ensuremath\geqslantN) universal quantum broadcasting of mixed states \ensuremathρ^\ensuremath\bigotimesN is proposed for a qubit system. The broadcasting of mixed states is universal and optimal in the sense that the shrinking factor is independent of the input state and achieves the upper bound. The quantum broadcasting of mixed qubits is a generalization of the universal quantum cloning machine for identical pure input states. A pure state decomposition of the identical mixed qubits \ensuremathρ^\ensuremath\bigotimesN is obtained.