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AIP conference proceedings

Quantum Control and Entanglement of Two Electrons in a Double Quantum Dot Structure

John Boviatsis, Evangelos Voutsinas, Theodore E. Simos, George Maroulis

Published Jan 1, 2007• 0 citations
Publisher

Abstract

The interaction of two electrons in a double quantum dot structure with an electromagnetic field is studied. Using proper approximations we obtain analytical solutions for the time evolution of the probabilities in the several quantum states and present conditions for the creation of maximally entangled two‐electron states.
DOI
10.1063/1.2836196

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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 a few scattered carriers produce decoherence of the whole two-dot system, a larger number of electrons injected from one lead with proper energy are able to recover its quantum coherence. Our numerical simulations are based on a real-space solution of the three-particle Schrödinger equation with open boundaries. The computed transmission amplitudes are inserted in the analytical expression for the system density matrix to evaluate the entanglement.