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arXiv · 1312.1711

Tunable Spin Qubit Coupling Mediated by a Multi-Electron Quantum Dot

V. Srinivasa·H. Xu·J. M. Taylor
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Abstract

We present an approach for entangling electron spin qubits localized on spatially separated impurity atoms or quantum dots via a multi-electron, two-level quantum dot. The effective exchange interaction mediated by the dot can be understood as the simplest manifestation of Ruderman-Kittel-Kasuya-Yosida exchange, and can be manipulated through gate voltage control of level splittings and tunneling amplitudes within the system. This provides both a high degree of tuneability and a means for realizing high-fidelity two-qubit gates between spatially separated spins, yielding an experimentally accessible method of coupling donor electron spins in silicon via a hybrid impurity-dot system.

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V. Srinivasa, H. Xu, J. M. Taylor. 2013-12-05. Tunable Spin Qubit Coupling Mediated by a Multi-Electron Quantum Dot. https://doi.org/10.1103/physrevlett.114.226803

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