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Two-spin entanglement induced by electron scattering in nanostructures

Gian Luca Giorgi·Ferdinando de Pasquale
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Abstract

We present a model where two magnetic impurities in a discrete tight-binding ring become entangled because of scattering processes associated to the injection of a conduction electron. We introduce a weak coupling approximation that allows us to solve the problem in a analytical way and compare the theory with the exact numerical results. We obtain the generation of entanglement both in a deterministic way and in a probabilistic one. The first case is intrinsically related to the structure of the two-impurity reduced density matrix, while the second one occurs when a projection on the electron state is performed.

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Gian Luca Giorgi, Ferdinando de Pasquale. 2006-10-23. Two-spin entanglement induced by electron scattering in nanostructures. https://doi.org/10.1103/physrevb.74.153308

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