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arXiv · 2206.11008

Optical Spin Initialisation and Readout with a Cavity-Coupled Quantum Dot in an In-Plane Magnetic Field

Samuel J. Sheldon·Alistair J. Brash·Maurice S. Skolnick·A. Mark Fox·Jake Iles-Smith
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Abstract

The spin of a charged semiconductor quantum dot (QD) coupled to an optical cavity is a promising candidate for high fidelity spin-photon interfaces; the cavity selectively modifies the decay rates of optical transitions such that spin initialisation, manipulation, and readout are all possible in a single magnetic field geometry. By performing cavity QED calculations, we show that a cavity with a single, linearly-polarised mode can simultaneously support both high-fidelity optical spin initialisation and readout in a single, in-plane (Voigt geometry) magnetic field. Furthermore, we demonstrate that single mode cavities always outperform bi-modal cavities in experimentally favourable driving regimes. Our analysis, when combined with established methods of control in a Voigt geometry field, provides optimal parameter regimes for high-fidelity initialisation and readout, and coherent control in both cavity configurations, providing insights for the design and development of QD spin-photon interfaces as the basis of quantum network nodes and for the generation of photonic graph states.

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Samuel J. Sheldon, Alistair J. Brash, Maurice S. Skolnick, A. Mark Fox, Jake Iles-Smith. 2022-06-22. Optical Spin Initialisation and Readout with a Cavity-Coupled Quantum Dot in an In-Plane Magnetic Field. https://arxiv.org/abs/2206.11008

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