Ziegler, J. and Kozlovsky, R. and Gorini, C. and Liu, M. -H. and Weishaupl, S. and Maier, H. and Fischer, R. and Kozlov, D. A. and Kvon, Z. D. and Mikhailov, N. and Dvoretsky, S. A. and Richter, K. and Weiss, D. (2018) Probing spin helical surface states in topological HgTe nanowires. PHYSICAL REVIEW B, 97 (3): 035157. ISSN 2469-9950, 2469-9969
Full text not available from this repository. (Request a copy)Abstract
Nanowires with helical surface states represent key prerequisites for observing and exploiting phase-coherent topological conductance phenomena, such as spin-momentum locked quantum transport or topological superconductivity. We demonstrate in a joint experimental and theoretical study that gated nanowires fabricated from high-mobility strained HgTe, known as a bulk topological insulator, indeed preserve the topological nature of the surface states, that moreover extend phase-coherently across the entire wire geometry. The phase-coherence lengths are enhanced up to 5 mu m when tuning the wires into the bulk gap, so as to single out topological transport. The nanowires exhibit distinct conductance oscillations, both as a function of the flux due to an axial magnetic field and of a gate voltage. The observed h/e-periodic Aharonov-Bohm-type modulations indicate surface-mediated quasiballistic transport. Furthermore, an in-depth analysis of the scaling of the observed gate-dependent conductance oscillations reveals the topological nature of these surface states. To this end we combined numerical tight-binding calculations of the quantum magnetoconductance with simulations of the electrostatics, accounting for the gate-induced inhomogeneous charge carrier densities around the wires. We find that helical transport prevails even for strongly inhomogeneous gating and is governed by flux-sensitive high-angular momentum surface states that extend around the entire wire circumference.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | INSULATOR NANORIBBONS; TRANSPORT; CONDUCTORS; |
| Subjects: | 500 Science > 530 Physics |
| Divisions: | Physics > Institute of Theroretical Physics > Chair Professor Richter > Group Klaus Richter Physics > Institute of Experimental and Applied Physics > Chair Professor Weiss > Group Dieter Weiss |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 20 Mar 2020 14:46 |
| Last Modified: | 20 Mar 2020 14:46 |
| URI: | https://pred.uni-regensburg.de/id/eprint/15174 |
Actions (login required)
 |
View Item |
