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arXiv · 1109.3342

Two-qubit Gate of Combined Single Spin Rotation and Inter-dot Spin Exchange in a Double Quantum Dot

R. Brunner·Y. -S. Shin·T. Obata·M. Pioro-Ladrière·T. Kubo·K. Yoshida·T. Taniyama·Y. Tokura·S. Tarucha
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Abstract

A crucial requirement for quantum information processing is the realization of multiple-qubit quantum gates. Here, we demonstrate an electron spin based all-electrical two-qubit gate consisting of single spin rotations and inter-dot spin exchange in a double quantum dot. A partially entangled output state is obtained by the application of the two-qubit gate to an initial, uncorrelated state. We find that the degree of entanglement is controllable by the exchange operation time. The approach represents a key step towards the realization of universal multiple qubit gates.

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R. Brunner, Y. -S. Shin, T. Obata, M. Pioro-Ladrière, T. Kubo, K. Yoshida, T. Taniyama, Y. Tokura, S. Tarucha. 2011-09-15. Two-qubit Gate of Combined Single Spin Rotation and Inter-dot Spin Exchange in a Double Quantum Dot. https://doi.org/10.1103/physrevlett.107.146801

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