%0 Conference Paper
%A Schäpers, Thomas
%T Phase-coherent transport in topological insulator nanoribbon-based structures
%M FZJ-2019-02895
%D 2019
%X Three-dimensional topological insulators have been subject of increased interest in the past few years due to their robust topologically protected surface states enclosing an insulating bulk. Especially the spin-momentum locking of these surface states makes this novel material class very attractive for spintronic applications. However, often the transport in the surface states is masked by a pronounced bulk conductance contribution owing to a relatively large background doping. By preparing topological insulator nanoribbons a more favorable surface-to-volume ratio can be achieved. In addition, these nanostructures allow to study confinement related carrier transport. Our topological insulator Bi2Te3 and Sb2Te3-based nanostructures were fabricated by selective-area molecular beam epitaxy using a SiO2/Si3N4-masked Si (111) substrate. We performed low temperature magnetotransport measurements on the nanoribbons, in order to investigate phase-coherent phenomena. Furthermore, nanoribbons were covered in-situ with superconducting electrodes to form topological Josephson junctions. Here, a clear Josephson supercurrent was observed. Measurements under microwave irradiation revealed a series of Shapiro steps. The observed missing of the first step indicates the presence of Majorana states.
%B Symposium on Quantum and Nanoelectronic Devices
%C 29 Apr 2019 - 29 Apr 2019, Lund (Sweden)
Y2 29 Apr 2019 - 29 Apr 2019
M2 Lund, Sweden
%F PUB:(DE-HGF)31
%9 Talk (non-conference)
%U https://juser.fz-juelich.de/record/862633