TY  - JOUR
AU  - Lüpke, Felix
AU  - Just, Sven
AU  - Eschbach, Markus
AU  - Heider, Tristan
AU  - Młyńczak, Ewa
AU  - Lanius, Martin
AU  - Schüffelgen, Peter
AU  - Rosenbach, Daniel
AU  - von den Driesch, Nils
AU  - Cherepanov, Vasily
AU  - Mussler, Gregor
AU  - Plucinski, Lukasz
AU  - Grützmacher, Detlev
AU  - Schneider, Claus M.
AU  - Tautz, F. Stefan
AU  - Voigtländer, Bert
TI  - In situ disentangling surface state transport channels of a topological insulator thin film by gating
JO  - npj quantum materials
VL  - 3
IS  - 1
SN  - 2397-4648
CY  - [London]
PB  - Nature Publishing Group
M1  - FZJ-2018-04886
SP  - 46
PY  - 2018
AB  - In the thin film limit, the surface state of a three-dimensional topological insulator gives rise to two parallel conduction channels at the top and bottom surface of the film, which are difficult to disentangle in transport experiments. Here, we present gate-dependent multi-tip scanning tunneling microscope transport measurements combined with photoemission experiments all performed in situ on pristine BiSbTe<sub>3</sub> thin films. To analyze the data, we develop a generic transport model including quantum capacitance effects. This approach allows us to quantify the gate-dependent conductivities, charge carrier concentrations, and mobilities for all relevant transport channels of three-dimensional topological insulator thin films (i.e., the two topological surface state channels, as well as the interior of the film). For the present sample, we find that the conductivity in the bottom surface state channel is minimized below a gate voltage of V<sub>gate</sub> = −34 V and the top surface state channel dominates the transport through the film.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000449705100001
DO  - DOI:10.1038/s41535-018-0116-1
UR  - https://juser.fz-juelich.de/record/851186
ER  -