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The Rochester Conferences on Coherence and Quantum Optics and the Quantum Information and Measurement meeting

A Spin Qubit Coupled to a Photonic Crystal Cavity

Timothy M. Sweeney, Sam Carter, Mijin Kim, Chul Soo Kim, Dmitry Solenov, Sophia E. Economou, T. L. Reinecke, Lily Yang, Allan S. Bracker, D. Gammon

Published Jan 1, 2013• 0 citations
Publisher

Abstract

We developed a charge-controlled quantum dot coupled to a photonic crystal cavity. We charge the dot with a single electron and perform optical spin initialization, rotation and measurement, demonstrating a spin qubit coupled to a cavity.
DOI
10.1364/cqo.2013.m5b.3

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The realization of quantum-photonic networks is a key challenge for optical quantum technologies. To scale such networks to many nodes and long distances, an efficient interface between stationary and flying qubits is necessary. One of the front-runners towards this goal is a spin-photon interface realised with a single charged QD with a localized electron spin that is strongly coupled to a micropillar cavity [1] . Through the strong spin-photon coupling, the polarization state of the optical field is controlled by the QD spin, thus modulating the cavity’s transmission properties. Controlling the polarization state over a wide angle is particularly useful for realizing high-fidelity polarization states and conditional phase quantum gates (e.g. CNOT) for photon-based quantum computing.
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