arXiv:1206.4442 · Physical Review Letters

Persistent Quantum Beats and Long-Distance Entanglement from Waveguide-Mediated Interactions

Huaixiu Zheng, Harold U. Baranger

Published Mar 12, 2013• 283 citations

Abstract

We study photon-photon correlations and entanglement generation in a one-dimensional waveguide coupled to two qubits with an arbitrary spatial separation. To treat the combination of nonlinear elements and 1D continuum, we develop a novel Green function method. The vacuum-mediated qubit-qubit interactions cause quantum beats to appear in the second-order correlation function. We go beyond the Markovian regime and observe that such quantum beats persist much longer than the qubit lifetime. A high degree of long-distance entanglement can be generated, increasing the potential of waveguide-QED systems for scalable quantum networking.

DOI: 10.1103/physrevlett.110.113601

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