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

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 نشر من قبل Roland Brunner RB
 تاريخ النشر 2011
  مجال البحث فيزياء
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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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