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Teleportation on a quantum dot array

F. de Pasquale·G. Giorgi·S. Paganelli
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Abstract

We present a model of quantum teleportation protocol based on a double quantum dot array. The unknown qubit is encoded using a pair of quantum dots, coupled by tunneling, with one excess electron. It is shown how to create maximally entangled states with this kind of qubits using an adiabatically increasing Coulomb repulsion between different pairs. This entangled states are exploited to perform teleportation again using an adiabatic coupling between them and the incoming unknown state. Finally, a sudden separation of Bob's qubit enables a time evolution of Alice's state providing a modified version of standard Bell measurement. Substituting the four quantum dots entangled state with a chain of coupled DQD's, a quantum channel with high fidelity arises from this scheme allowing the transmission over long distances.

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F. de Pasquale, G. Giorgi, S. Paganelli. 2004-02-25. Teleportation on a quantum dot array. https://doi.org/10.1103/physrevlett.93.120502

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