Abstract
Scattering of a ballistic electron by the quantum-dot spin qubits fixed in a graphene nanoribbon is investigated theoretically. Two simple cases are investigated in details: scattering from a static quantum dot and scattering from two static quantum dots located at a fixed distance from each other. For the first case, it is shown that the Klein tunneling in a graphene sheet leads to a final entangled state for the reflected and/or transmitted electrons. The amount of the generated entanglement through the scattering process is a function of the incident angle for the ballistic electrons. For the second case, it is shown that the created correlation between the quantum dots is a periodic function of their distance. For frontal incident electrons in both cases, there is not any reflection and the Klein tunneling effect leads to a final well-correlated state for the scattering system.
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One of the authors, M. Sheikhali, would like to acknowledge the office of graduate studies at the University of Isfahan for their support and research facilities.
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Ghanbari-Adivi, E., Soltani, M. & Sheikhali, M. Entanglement generation due to the Klein tunneling in a graphene sheet. Quantum Inf Process 15, 2377–2391 (2016). https://doi.org/10.1007/s11128-016-1280-5
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DOI: https://doi.org/10.1007/s11128-016-1280-5