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arXiv · 1812.00496

Quantum pumping with adiabatically modulated barriers in three-band pseudospin-1 Dirac-Weyl systems

Xiaomei Chen·Rui Zhu
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Abstract

In this work, pumped currents of the adiabatically-driven double-barrier structure based on the pseudospin-1 Dirac-Weyl fermions are studied. As a result of the three-band dispersion and hence the unique properties of pseudospin-1 Dirac-Weyl quasiparticles, sharp current-direction reversal is found at certain parameter settings especially at the Dirac point of the band structure, where apexes of the two cones touches at the flat band. Such a behavior can be interpreted consistently by the Berry phase of the scattering matrix and the classical turnstile mechanism.

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Xiaomei Chen, Rui Zhu. 2018-12-03. Quantum pumping with adiabatically modulated barriers in three-band pseudospin-1 Dirac-Weyl systems. https://doi.org/10.3390/e21020209

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