Swapping and entangling qubits of single photons and atoms

T. W. Chen; C. K. Law; P. T. Leung

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arXiv · quant-ph/0311156

Swapping and entangling qubits of single photons and atoms

T. W. Chen·C. K. Law·P. T. Leung

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Abstract

A scheme is proposed here to achieve swapping and entangling of photonic and atomic qubits with high fidelity. The mechanism is based on the scattering of a single photon from a $Λ$-type three-level atom. The evolution of the coupled system is analyzed by projecting the quantum state onto a `bright' and a `dark' state. Quantum interference of these two states, which is determined by a frequency-dependent phase angle, can be exploited to perform various two-qubit transformations. It is remarkable that the probability of success of such transformations can approach unity in the strong coupling cavity QED regime.

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T. W. Chen, C. K. Law, P. T. Leung. 2003-11-23. Swapping and entangling qubits of single photons and atoms. https://arxiv.org/abs/quant-ph/0311156

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