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arXiv · 1408.5160

Optical Manipulation of Quantum Dot Electron Spin Qubits Using Microcavity Quantum Well Exciton-Polaritons

Shruti Puri·Peter L. McMahon·Yoshihisa Yamamoto
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Abstract

In this paper we introduce and analyze a new system design for quantum-dot-based qubits that simultaneously supports scalable one-qubit and two-qubit gates, and single-shot qubit measurement. All three key processes (one-qubit gates, two-qubit gates, and qubit measurement) rely on the interaction between the electron in each quantum dot and exciton-polaritons formed in a quantum well situated near the quantum dots. A key novel feature of our proposed system is the use of polariton traps, which we show enhances the quantum-dot--quantum-well interaction by a factor of 10 and consequently results in $100 \times$ faster two-qubit gates. We also introduce a novel one-qubit gate that is based on a combination of optical and microwave control, which is supported in the same device and system configuration as the other operations, in contrast to the conventional one-qubit gate that is based on all-optical control.

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Shruti Puri, Peter L. McMahon, Yoshihisa Yamamoto. 2017-05-07. Optical Manipulation of Quantum Dot Electron Spin Qubits Using Microcavity Quantum Well Exciton-Polaritons. https://doi.org/10.1103/physrevb.95.125410

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