Thermal entanglement between alternate qubits of a four-qubit Heisenberg XX chain in a magnetic field

Journal Article · Tue Mar 01 00:00:00 EST 2005 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.71.034311· OSTI ID:20650517

Min, Cao; Shiqun, Zhu ^[1]

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1. School of Physical Science and Technology, Suzhou University, Suzhou, Jiangsu 215006 (China)

The concurrence of two alternate qubits in a four-qubit Heisenberg XX chain is investigated when a uniform magnetic field B is included. It is found that there is no thermal entanglement between alternate qubits if B is close to zero. A magnetic field can induce entanglement in a certain range both for the antiferromagnetic and ferromagnetic cases. Near zero temperature, the entanglement undergoes two sudden changes with increasing value of the magnetic field B. This is due to the changes in the ground state. This novel property may be used as a quantum entanglement switch. The anisotropy in the system can also induce the entanglement between two alternate qubits.

• OSTI ID: 20650517
• Journal Information: Physical Review. A, Vol. 71, Issue 3; Other Information: DOI: 10.1103/PhysRevA.71.034311; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
36 MATERIALS SCIENCE
ANISOTROPY
ANTIFERROMAGNETISM
CORRELATIONS
GROUND STATES
HEISENBERG MODEL
INFORMATION THEORY
MAGNETIC FIELDS
QUANTUM MECHANICS
QUANTUM NUMBERS