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arXiv · 1505.01513

Transient and steady-state entanglement mediated by three-dimensional plasmonic waveguides

S. Ali Hassani Gangaraj·Andrei Nemilentsau·George W. Hanson·Stephen Hughes
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Abstract

Entanglement between two qubits (two level atoms) mediated by surface plasmons in three-dimensional plasmonic waveguides is studied using a quantum master equation formalism. Two types of waveguides, a nanowire and a V-shaped channel cut in a flat metal plane, are considered. The Green functions for the waveguides, which rigorously describes the dissipative qubit environment, are calculated numerically using a direct finite-difference time-domain (FDTD) solution of Maxwell's equations. Finite-length effects are shown to play a crucial role in enhancing entanglement, and resonant-length plasmonic waveguides can provide higher entanglement between qubits than infinite-length waveguides. It is also shown that coupling slots can improve entanglement via stronger qubit-waveguide coupling, for both the infinite- and finite-waveguide cases.

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S. Ali Hassani Gangaraj, Andrei Nemilentsau, George W. Hanson, Stephen Hughes. 2015-05-06. Transient and steady-state entanglement mediated by three-dimensional plasmonic waveguides. https://doi.org/10.1364/oe.23.022330

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