High-fidelity entanglement of two spectrally-distinct solid state emitters

Daniel R. E. Hodgson; Pieter Kok

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arXiv · 2610.31283

High-fidelity entanglement of two spectrally-distinct solid state emitters

Daniel R. E. Hodgson·Pieter Kok

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Abstract

Solid state quantum emitters with electronic spin properties can be entangled using optical interferometric which-path erasure techniques that rely on identical frequencies and linewidths of the emitters. This promises a powerful, fast and scalable platform for quantum technologies. Using current protocols, a pair of emitters embedded in a waveguide interferometer can be deterministically prepared in a maximally entangled state. However, the amount of entanglement diminishes rapidly with increasing separation of the emission lines and variations in the linewidths of the emitters. Solid state emitters such as quantum dots are subject to intrinsic variations in the fabrication process. Therefore, manufacturing the required number of identical emitters on a chip is not scalable. In this Letter, we present a method that uses readily available pairs of entangled photons to entangle solid state emitters with large transition frequency separations and linewidth variations, circumventing the need to fabricate optically identical emitters. We demonstrate a concurrence of C = 0.95 for typical quantum dots using narrowband photon inputs.

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Daniel R. E. Hodgson, Pieter Kok. 2026-10-22. High-fidelity entanglement of two spectrally-distinct solid state emitters. https://arxiv.org/abs/2610.31283

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