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arXiv · 2212.11026

Random spin-orbit gates in the system of a Topological insulator and a Quantum dot

S. Wolski·M. Inglot·C. Jasiukiewicz·K. A. Kouzakov·T. Masłowski·T. Szczepański·S. Stagraczyński·R. Stagraczyński·V. K. Dugaev·L. Chotorlishvili
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Abstract

The spin-dependent scattering process in a system of topological insulator and quantum dot is studied. The unitary scattering process is viewed as a gate transformation applied to an initial state of two electrons. Due to the randomness imposed through the impurities and alloying-induced effects of band parameters, the formalism of the random unitary gates is implemented. For quantifying entanglement in the system, we explored concurrence and ensemble-averaged R\'enyi entropy. We found that applied external magnetic field leads to long-range entanglement on the distances much larger than the confinement length. We showed that topological features of itinerant electrons sustain the formation of robust long-distance entanglement, which survives even in the presence of a strong disorder.

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S. Wolski, M. Inglot, C. Jasiukiewicz, K. A. Kouzakov, T. Masłowski, T. Szczepański, S. Stagraczyński, R. Stagraczyński, V. K. Dugaev, L. Chotorlishvili. 2022-12-21. Random spin-orbit gates in the system of a Topological insulator and a Quantum dot. https://doi.org/10.1103/physrevb.106.224418

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