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arXiv · 1706.02486

Protocol for generating multi-photon entangled states from quantum dots in the presence of nuclear spin fluctuations

Emil V. Denning·Jake Iles-Smith·Dara P. S. McCutcheon·Jesper Mork
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Abstract

Multi-photon entangled states are a crucial resource for many applications in quantum information science. Semiconductor quantum dots offer a promising route to generate such states by mediating photon-photon correlations via a confined electron spin, but dephasing caused by the host nuclear spin environment typically limits coherence (and hence entanglement) between photons to the spin $T_2^*$ time of a few nanoseconds. We propose a protocol for the deterministic generation of multi-photon entangled states that is inherently robust against the dominating slow nuclear spin environment fluctuations, meaning that coherence and entanglement is instead limited only by the much longer spin $T_2$ time of microseconds. Unlike previous protocols, the present scheme allows for the generation of very low error probability polarisation encoded three-photon GHZ states and larger entangled states, without the need for spin echo or nuclear spin calming techniques.

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Emil V. Denning, Jake Iles-Smith, Dara P. S. McCutcheon, Jesper Mork. 2017-06-08. Protocol for generating multi-photon entangled states from quantum dots in the presence of nuclear spin fluctuations. https://doi.org/10.1103/physreva.96.062329

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