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arXiv · 1406.0714

Polarization engineering in photonic crystal waveguides for spin-photon entanglers

Andrew B. Young·Arthur Thijssen·Daryl M. Beggs·Petros Androvitsaneas·L. Kuipers·John G. Rarity·Stephen Hughes·Ruth Oulton
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Abstract

By performing a full analysis of the projected local density of states (LDOS) in a photonic crystal waveguide, we show that phase plays a crucial role in the symmetry of the light-matter interaction. By considering a quantum dot (QD) spin coupled to a photonic crystal waveguide (PCW) mode, we demonstrate that the light-matter interaction can be asymmetric, leading to unidirectional emission and a deterministic entangled photon source. Further we show that understanding the phase associated with both the LDOS and the QD spin is essential for a range of devices that that can be realised with a QD in a PCW. We also show how quantum entanglement can completely reverse photon propagation direction, and highlight a fundamental breakdown of the semiclassical dipole approximation for describing light-matter interactions in these spin dependent systems.

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Andrew B. Young, Arthur Thijssen, Daryl M. Beggs, Petros Androvitsaneas, L. Kuipers, John G. Rarity, Stephen Hughes, Ruth Oulton. 2014-06-03. Polarization engineering in photonic crystal waveguides for spin-photon entanglers. https://doi.org/10.1103/physrevlett.115.153901

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