Quantum discord in finiteXYchains

2010/10/19 by L. Ciliberti, R. Rossignoli, N. Canosa · 2 citations
Computer Science · Mathematics · Physics and Astronomy · #Algorithm #Condensed matter physics #Limit (mathematics) #Mathematical analysis #Mathematics #Physics #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum and electron transport phenomena #Quantum mechanics #Spins #quant-ph

paper · pdf · doi:10.1103/physreva.82.042316

published as Physical Review A 82, 042316 (2010) · 9 pages, 6 figures

openalex publication_date 2010/10/19 · arxiv created 2011/04/29 · arxiv updated 2015/05/28 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

We examine the quantum discord between two spins in the exact ground state of finite spin-1/2 arrays with anisotropic XY couplings in a transverse field B. It is shown that in the vicinity of the factorizing field B_s, the discord approaches a common finite non-negligible limit which is independent of the pair separation and the coupling range. An analytic expression of this limit is provided. The discord of a mixture of aligned pairs in two different directions, crucial for the previous results, is analyzed in detail, including the evaluation of coherence effects, relevant in small samples and responsible for a parity splitting at B_s. Exact results for finite chains with first-neighbor and full-range couplings and their interpretation in terms of such mixtures are provided.

Citations

• Validity of many-body approximation methods for a solvable model
• Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels
• Thermal and Magnetic Quantum Discord in Heisenberg models
• Entanglement of Formation of an Arbitrary State of Two Qubits
• Signatures of nonclassicality in mixed-state quantum computation
• Two-spin entanglement distribution near factorized states
• General Monogamy Inequality for Bipartite Qubit Entanglement
• Quantum states with Einstein-Podolsky-Rosen correlations admitting a hidden-variable model
• Entanglement of finite cyclic chains at factorizing fields
• Entanglement of a Pair of Quantum Bits
• Decoherence, einselection, and the quantum origins of the classical
• Classical, quantum and total correlations
• Two soluble models of an antiferromagnetic chain
• Distributed Entanglement
• Quantum coding

Cited by

• Enhancing the geometric quantum discord in the Heisenberg XX chain by Dzyaloshinsky–Moriya interaction
• Measures and applications of quantum correlations