Dynamics of two qubits in a spin-bath of Quantum anisotropic Heisenberg XY coupling type

Abstract

The dynamics of two 1/2-spin qubits under the influence of a quantum Heisenberg XY type spin-bath is studied. After the Holstein-Primakoff transformation, a novel numerical polynomial scheme is used to give the time-evolution calculation of the center qubits initially prepared in a product state or a Bell state. Then the concurrence of the two qubits, the $z$-component moment of either of the subsystem spins and the fidelity of the subsystem are shown, which exhibit sensitive dependence on the anisotropic parameter, the temperature, the coupling strength and the initial state. It is found that (i) the larger the anisotropic parameter $\gamma$, the bigger the probability of maintaining the initial state of the two qubits; (ii) with increasing temperature $T$, the bath plays a more strong destroy effect on the dynamics of the subsystem, so does the interaction $g_0$ between the subsystem and the bath; (iii) the time evolution of the subsystem is dependent on the initial state. The revival of the concurrence does not always means the restore of the state. Further, the dynamical properties of the subsystem should be judged by the combination of concurrence and fidelity.

arXiv comment16pages,9figures. Phys. Rev. B 75, 174425

References in corpus (18)

• Entanglement of Formation of an Arbitrary State of Two Qubits
• Quantum Computation with Quantum Dots
• Concentrating Partial Entanglement by Local Operations
• Entanglement of a Pair of Quantum Bits
• Coupled quantum dots as quantum gates
• Quantum data processing and error correction
• Entanglement in the Quantum Heisenberg XY model
• Theory of the spin bath
• Non-Markovian dynamics in a spin star system: Exact solution and approximation techniques
• Electron spin dynamics in quantum dots and related nanostructures due to hyperfine interaction with nuclei
• An efficient scheme for numerical simulations of the spin-bath decoherence
• Reducing Constraints on Quantum Computer Design by Encoded Selective Recoupling
• Non-Markovian reduced dynamics and entanglement evolution of two coupled spins in a quantum spin environment
• Two qubits entanglement dynamics in a symmetry-broken environment
• Exact quantum jump approach to open systems in Bosonic and spin baths
• Suppression of decoherence via strong intra-environmental coupling
• Global entanglement in XXZ chains
• Polynomial scheme for time evolution of open and closed quantum systems

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