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arXiv · 1312.4570

Orbital entanglement and electron localization in quantum wires

Alberto Aleta·Héctor Villarubia-Rojo·Diego Frustaglia·Víctor A. Gopar
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Abstract

We study the signatures of disorder in the production of orbital electron entanglement in quantum wires. Disordered entanglers suffer the effects of localization of the electron wave function and random fluctuations in the entanglement production. This manifests in the statistics of the concurrence, a measure of the produced two-qubit entanglement. We calculate the concurrence distribution as a function of the disorder strength within a random-matrix approach. We also identify significant constraints on the entanglement production as a consequence of the breaking/preservation of time-reversal invariance. Additionally, our theoretical results are independently supported by simulations of disordered quantum wires based on a tight-binding model.

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Alberto Aleta, Héctor Villarubia-Rojo, Diego Frustaglia, Víctor A. Gopar. 2013-12-16. Orbital entanglement and electron localization in quantum wires. https://doi.org/10.1103/physrevb.89.075429

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