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arXiv · 2301.04444

Entanglement properties of a quantum-dot biexciton cascade in a chiral nanophotonic waveguide

Eva M. González-Ruiz·Freja T. Østfeldt·Ravitej Uppu·Peter Lodahl·Anders S. Sørensen
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Abstract

We analyse the entanglement properties of deterministic path-entangled photonic states generated by coupling the emission of a quantum-dot biexciton cascade to a chiral nanophotonic waveguide, as implemented by {\O}stfeldt et al. [PRX Quantum 3, 020363 (2022)]. We model the degree of entanglement through the concurrence of the two-photon entangled state in the presence of realistic experimental imperfections. The model accounts for imperfect chiral emitter-photon interactions in the waveguide and the asymmetric coupling of the exciton levels introduced by fine-structure splitting along with time-jitter in the detection of photons. The analysis shows that the approach offers a promising platform for deterministically generating entanglement in integrated nanophotonic systems in the presence of realistic experimental imperfections.

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Eva M. González-Ruiz, Freja T. Østfeldt, Ravitej Uppu, Peter Lodahl, Anders S. Sørensen. 2023-01-11. Entanglement properties of a quantum-dot biexciton cascade in a chiral nanophotonic waveguide. https://doi.org/10.1103/physreva.108.013507

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