Aharonov-Bohm oscillations in disordered topological insulator nanowires

Abstract

A direct signature of electron transport at the metallic surface of a topological insulator is the Aharonov-Bohm oscillation observed in a recent study of Bi_2Se_3 nanowires [Peng et al., Nature Mater. 9, 225 (2010)] where conductance was found to oscillate as a function of magnetic flux $\varphi$ through the wire, with a period of one flux quantum ${\varphi }_0=h/e$ and maximum conductance at zero flux. This seemingly agrees neither with diffusive theory, which would predict a period of half a flux quantum, nor with ballistic theory, which in the simplest form predicts a period of ${\varphi }_0$ but a minimum at zero flux due to a nontrivial Berry phase in topological insulators. We show how h/e and h/2e flux oscillations of the conductance depend on doping and disorder strength, provide a possible explanation for the experiments, and discuss further experiments that could verify the theory.

4 pages, 3 figures; v2. added data for weak antilocalization

References in corpus (4)

• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• Topological delocalization of two-dimensional massless Dirac fermions
• Spin-charge Separated Solitons in a Topological Band Insulator
• Crossover from quantum to Boltzmann transport in graphene

Cited by in corpus (2)

• Anomalous Aharonov-Bohm conductance oscillations from topological insulator surface states
• Full electrical control of Charge and Spin conductance through Interferometry of Edge States in Topological Insulators