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arXiv · 1710.06387

On controlling the bound states in quantum-dot hybrid-nanowire

Andrzej Ptok·Aksel Kobiałka·Tadeusz Domański
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Abstract

Recent experiments using the quantum dot coupled to the topological superconducting nanowire [M.T. Deng et al., Science 354, 1557 (2016)}] revealed that zero-energy bound state coalesces from the Andreev bound states. Such quasiparticle states, present in the quantum dot, can be controlled by the magnetic and electrostatic means. We use microscopic model of the quantum-dot--nanowire structure to reproduce the experimental results, applying the Bogoliubov--de~Gennes technique. This is done by studying the gate voltage dependence of the various types of bound states and mutual influence between them. We show that the zero energy bound states can emerge from the Andreev bound states in topologically trivial phase and can be controlled using various means. In non-trivial topological phase we show the possible resonance between this zero energy levels with Majorana bound states. We discuss and explain this phenomena as a result of dominant spin character of discussed bound states. Presented results can be applied in experimental studies by using the proposed nanodevice.

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Andrzej Ptok, Aksel Kobiałka, Tadeusz Domański. 2017-11-01. On controlling the bound states in quantum-dot hybrid-nanowire. https://doi.org/10.1103/physrevb.96.195430

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