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arXiv · 1008.5237

On demand entanglement in double quantum dots via coherent carrier scattering

Fabrizio Buscemi·Paolo Bordone·Andrea Bertoni
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Abstract

We show how two qubits encoded in the orbital states of two quantum dots can be entangled or disentangled in a controlled way through their interaction with a weak electron current. The transmission/reflection spectrum of each scattered electron, acting as an entanglement mediator between the dots, shows a signature of the dot-dot entangled state. Strikingly, while few scattered carriers produce decoherence of the whole two-dots system, a larger number of electrons injected from one lead with proper energy is able to recover its quantum coherence. Our numerical simulations are based on a real-space solution of the three-particle Schroedinger equation with open boundaries. The computed transmission amplitudes are inserted in the analytical expression of the system density matrix in order to evaluate the entanglement.

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Fabrizio Buscemi, Paolo Bordone, Andrea Bertoni. 2010-11-30. On demand entanglement in double quantum dots via coherent carrier scattering. https://doi.org/10.1088/1367-2630%2F13%2F1%2F013023

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