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Electron Entanglement via a Quantum Dot

William D. Oliver·F. Yamaguchi·Y. Yamamoto
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Abstract

This Letter presents a method of electron entanglement generation. The system under consideration is a single-level quantum dot with one input and two output leads. The leads are arranged such that the dot is empty, single electron tunneling is suppressed by energy conservation, and two-electron virtual co-tunneling is allowed. This yields a pure, non-local spin-singlet state at the output leads. Coulomb interaction is the nonlinearity essential for entanglement generation, and, in its absence, the singlet state vanishes. This type of electron entanglement is a four-wave mixing process analogous to the photon entanglement generated by a Chi-3 parametric amplifier.

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William D. Oliver, F. Yamaguchi, Y. Yamamoto. 2001-07-16. Electron Entanglement via a Quantum Dot. https://doi.org/10.1103/physrevlett.88.037901

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