Quantum and classical thermal correlations in the XY spin-(1/2) chain

Journal Article · Thu Jul 15 04:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.82.012106· OSTI ID:21440459

Maziero, J; Guzman, H C; Celeri, L C; Serra, R M ^[1]; Sarandy, M S ^[2]

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1. Centro de Cie circumflex ncias Naturais e Humanas, Universidade Federal do ABC, R. Santa Adelia 166, 09210-170, Santo Andre, Sao Paulo (Brazil)
2. Instituto de Fisica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Gragoata, 24210-346, Niteroi, Rio de Janeiro (Brazil)

We investigate pairwise quantum correlation as measured by the quantum discord as well as its classical counterpart in the thermodynamic limit of anisotropic XY spin-1/2 chains in a transverse magnetic field for both zero and finite temperatures. Analytical expressions for both classical and quantum correlations are obtained for spin pairs at any distance. In the case of zero temperature, it is shown that the quantum discord for spin pairs farther than second neighbors is able to characterize a quantum phase transition, even though pairwise entanglement is absent for such distances. For finite temperatures, we show that quantum correlations can be increased with temperature in the presence of a magnetic field. Moreover, in the XX limit, thermal quantum discord is found to be dominant over classical correlation while the opposite scenario takes place for the transverse field Ising model limit.

• OSTI ID: 21440459
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 1 Vol. 82; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANGULAR MOMENTUM
ANISOTROPY
CORRELATIONS
CRYSTAL MODELS
DISTANCE
ISING MODEL
MAGNETIC FIELDS
MATHEMATICAL MODELS
MECHANICS
PARTICLE PROPERTIES
PHASE TRANSFORMATIONS
QUANTUM ENTANGLEMENT
QUANTUM MECHANICS
SPIN
TEMPERATURE ZERO K