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arXiv · 1504.08030

Pseudo-ballistic transport in 3D topological insulator quantum wires

Joseph Dufouleur·Louis Veyrat·Emmanouil Xypakis·Jens H. Bardarson·Christian Nowka·Silke Hampel·Barbara Eichler·Oliver G. Schmidt·Bernd Büchner·Romain Giraud
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Abstract

Quantum conductance fluctuations are investigated in disordered 3D topological insulator quantum wires. Both experiments and theory reveal a new transport regime in a mesoscopic conductor, pseudo-ballistic transport, for which ballistic properties persist beyond the transport mean free path, characteristic of diffusive transport. It results in non-universal conductance fluctuations due to quasi-1D surface modes, as observed in long and narrow Bi$_2$Se$_3$ nanoribbons. Spin helical Dirac fermions in quantum wires retain pseudo-ballistic properties over an unusually broad energy range, due to strong quantum confinement and weak momentum scattering.

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Joseph Dufouleur, Louis Veyrat, Emmanouil Xypakis, Jens H. Bardarson, Christian Nowka, Silke Hampel, Barbara Eichler, Oliver G. Schmidt, Bernd Büchner, Romain Giraud. 2015-04-29. Pseudo-ballistic transport in 3D topological insulator quantum wires. https://doi.org/10.1038/srep45276

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