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arXiv · 2310.16930

Spin-photon entanglement with direct photon emission in the telecom C-band

P. Laccotripes·T. Müller·R. M. Stevenson·J. Skiba-Szymanska·D. A. Ritchie·A. J. Shields
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Abstract

The ever-evolving demands for computational power and for a securely connected world dictate the development of quantum networks where entanglement is distributed between connected parties. Solid-state quantum emitters in the telecom C-band are a promising platform for quantum communication applications due to the minimal absorption of photons at these wavelengths, "on-demand" generation of single photon flying qubits, and ease of integration with existing network infrastructure. Here, we use an InAs/InP quantum dot to implement an optically active spin-qubit, based on a negatively charged exciton where the electron spin degeneracy is lifted using a Voigt magnetic field. We investigate the coherent interactions of the spin-qubit system under resonant excitation, demonstrating high fidelity spin initialisation and coherent control using picosecond pulses. We further use these tools to measure the coherence of a single, undisturbed electron spin in our system. Finally, we report the first demonstration of spin-photon entanglement in a solid-state system capable of direct emission into the telecom C-band.

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P. Laccotripes, T. Müller, R. M. Stevenson, J. Skiba-Szymanska, D. A. Ritchie, A. J. Shields. 2023-10-25. Spin-photon entanglement with direct photon emission in the telecom C-band. https://doi.org/10.1038/s41467-024-53964-1

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