2015/02/28 by Paulo E. M. F. Mendonca, Paulo E. M. F. Mendonça, Seyed Mohammad Hashemi Rafsanjani +3
Chemistry · Computer Science · Mathematics · Physics and Astronomy · #Algorithm #Chemistry #Concurrence #Density matrix #Discrete mathematics #Law #Mathematical optimization #Mathematics #Multipartite #Operator (biology) #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum entanglement #Quantum mechanics #Qubit #Semidefinite programming #State (computer science) #Transformation (genetics) #Unitary state #Unitary transformation #W state #quant-ph
paper · pdf · doi:10.1088/1751-8113/48/21/215304
published as J. Phys. A: Math. Theor. 48 (2015) 215304 · 22 pages, 2 figures. v2 (published version): connection with "biseparability from spectrum" dropped from the concluding remarks since, in the last paragraph os Sec. 3, an argument was included to demonstrate that N-qubit X-MEMS are generally not N-qubit MEMS
openalex publication_date 2015/05/08 · arxiv created 2015/05/12 · arxiv updated 2015/05/14 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
For every possible spectrum of -dimensional density operators, we construct an N -qubit X-state of the same spectrum and maximal genuine multipartite (GM-) concurrence, hence characterizing a global unitary transformation that—constrained to output X-states—maximizes the GM-concurrence of an arbitrary input mixed state of N qubits. We also apply semidefinite programming methods to obtain N -qubit X-states with maximal GM-concurrence for a given purity and to provide an alternative proof of optimality of a recently proposed set of density matrices for the purpose, the so-called X-MEMS. Furthermore, we introduce a numerical strategy to tailor a quantum operation that converts between any two given density matrices using a relatively small number of Kraus operators. We apply our strategy to design short operator-sum representations for the transformation between any given N -qubit mixed state and a corresponding X-MEMS of the same purity.