Quasi-ballistic transport of Dirac fermions in a Bi2Se3 nanowire

J. Dufouleur (1) , L. Veyrat (1) , A. Teichgräber (1) , S. Neuhaus (1) , C. Nowka (1) , S. Hampel (1) , Jérôme Cayssol (2, 3) , J. Schumann (1) , B. Eichler (1) , O. G. Schmidt (1) , B. Büchner (1, 4) , R. Giraud (1, 5)

1 IFW Dresden - Leibniz Institute for Solid State and Materials Research
2 LOMA - Laboratoire Ondes et Matière d'Aquitaine
3 MPI-PKS - Max-Planck-Institut für Physik komplexer Systeme
4 Department of Physics [TU Dresden]
5 LPN - Laboratoire de photonique et de nanostructures

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.

Mots clés: Quantum wires; Phases: geometric; dynamic or topological; Electronic transport in mesoscopic systems

Domaines: Autre [cond-mat.other]

J. Dufouleur, L. Veyrat, A. Teichgräber, S. Neuhaus, C. Nowka, et al.. Quasi-ballistic transport of Dirac fermions in a Bi2Se3 nanowire. Physical Review Letters, 2013, 110 (18), pp.186806 (1-5). ⟨10.1103/PhysRevLett.110.186806⟩. ⟨hal-00838133⟩