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arXiv · 1211.7316

Quasi-ballistic transport of Dirac fermions in a Bi2Se3 nanowire

J. Dufouleur·L. Veyrat·A. Teichgraeber·S. Neuhaus·C. Nowka·S. Hampel·J. Cayssol·J. Schumann·B. Eichler·O. Schmidt·B. Buechner·R. Giraud
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Abstract

Quantum coherent transport of Dirac fermions in a mesoscopic nanowire of the 3D topological insulator Bi2Se3 is studied in the weak-disorder limit. At very low temperatures, many harmonics are evidenced in the Fourier transform of Aharonov-Bohm oscillations, revealing the long phase-coherence length of surface states. Remarkably, from their exponential temperature dependence, we infer an unusual 1/T power law for the phase coherence length. This decoherence is typical for quasi-ballistic fermions weakly coupled to the dynamics of their environment.

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J. Dufouleur, L. Veyrat, A. Teichgraeber, S. Neuhaus, C. Nowka, S. Hampel, J. Cayssol, J. Schumann, B. Eichler, O. Schmidt, B. Buechner, R. Giraud. 2012-11-30. Quasi-ballistic transport of Dirac fermions in a Bi2Se3 nanowire. https://doi.org/10.1103/physrevlett.110.186806

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