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arXiv · 1709.06369

Spin-photon interface and spin-controlled photon switching in a nanobeam waveguide

Alisa Javadi·Dapeng Ding·Martin Hayhurst Appel·Sahand Mahmoodian·Matthias C. Löbl·Immo Söllner·Rüdiger Schott·Camille Papon·Tommaso Pregnolato·Søren Stobbe·Leonardo Midolo·Tim Schröder·Andreas D. Wieck·Arne Ludwig·Richard J. Warburton·Peter Lodahl
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Abstract

Access to the electron spin is at the heart of many protocols for integrated and distributed quantum-information processing [1-4]. For instance, interfacing the spin-state of an electron and a photon can be utilized to perform quantum gates between photons [2,5] or to entangle remote spin states [6-9]. Ultimately, a quantum network of entangled spins constitutes a new paradigm in quantum optics [1]. Towards this goal, an integrated spin-photon interface would be a major leap forward. Here we demonstrate an efficient and optically programmable interface between the spin of an electron in a quantum dot and photons in a nanophotonic waveguide. The spin can be deterministically prepared with a fidelity of 96\%. Subsequently the system is used to implement a "single-spin photonic switch", where the spin state of the electron directs the flow of photons through the waveguide. The spin-photon interface may enable on-chip photon-photon gates [2], single-photon transistors [10], and efficient photonic cluster state generation [11].

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BibTeXRIS

Alisa Javadi, Dapeng Ding, Martin Hayhurst Appel, Sahand Mahmoodian, Matthias C. Löbl, Immo Söllner, Rüdiger Schott, Camille Papon, Tommaso Pregnolato, Søren Stobbe, Leonardo Midolo, Tim Schröder, Andreas D. Wieck, Arne Ludwig, Richard J. Warburton, Peter Lodahl. 2017-09-19. Spin-photon interface and spin-controlled photon switching in a nanobeam waveguide. https://doi.org/10.1038/s41565-018-0091-5

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