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Entanglement between qubits induced by a common environment with a gap

Sangchul Oh·Jaewan Kim
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Abstract

We study a system of two qubits interacting with a common environment, described by a two-spin boson model. We demonstrate two competing roles of the environment: inducing entanglement between the two qubits and making them decoherent. For the environment of a single harmonic oscillator, if its frequency is commensurate with the induced two-qubit coupling strength, the two qubits could be maximally entangled and the environment could be separable. In the case of the environment of a bosonic bath, the gap of its spectral density function is essential to generate entanglement between two qubits at equilibrium and for it to be used as a quantum data bus.

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Sangchul Oh, Jaewan Kim. 2006-05-03. Entanglement between qubits induced by a common environment with a gap. https://doi.org/10.1103/physreva.73.062306

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