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arXiv · 1812.07540

Quantum Interface of an Electron and a Nuclear Ensemble

Dorian Gangloff·Gabriel Éthier-Majcher·Constantin Lang·Emil Denning·Jonathan Bodey·Daniel Jackson·Edmund Clarke·Maxime Hugues·Claire Le Gall·Mete Atatüre
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Abstract

Coherent excitation of an ensemble of quantum objects underpins quantum many-body phenomena, and offers the opportunity to realize a quantum memory to store information from a qubit. Thus far, a deterministic and coherent interface between a single quantum system, e.g. a qubit, and such an ensemble has remained elusive. We first use an electron to cool the mesoscopic nuclear-spin ensemble of a semiconductor quantum dot to the nuclear sideband-resolved regime. We then implement an all-optical approach to access these individual quantized electronic-nuclear spin transitions. Finally, we perform coherent optical rotations of a single collective nuclear spin excitation corresponding to a spin wave called a nuclear magnon. These results constitute the building blocks of a dedicated local memory per quantum-dot spin qubit and promise a solid-state platform for quantum-state engineering of isolated many-body systems.

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Dorian Gangloff, Gabriel Éthier-Majcher, Constantin Lang, Emil Denning, Jonathan Bodey, Daniel Jackson, Edmund Clarke, Maxime Hugues, Claire Le Gall, Mete Atatüre. 2018-12-18. Quantum Interface of an Electron and a Nuclear Ensemble. https://doi.org/10.1126/science.aaw2906

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