TY  - JOUR
AU  - Eschbach, Markus
AU  - Młyńczak, Ewa
AU  - Kellner, Jens
AU  - Kampmeier, Jörn
AU  - Lanius, Martin
AU  - Neumann, Elmar
AU  - Weyrich, Christian
AU  - Gehlmann, Mathias
AU  - Gospodarič, Pika
AU  - Döring, Sven
AU  - Mussler, Gregor
AU  - Demarina, Nataliya
AU  - Luysberg, Martina
AU  - Bihlmayer, Gustav
AU  - Schäpers, Thomas
AU  - Plucinski, Lukasz
AU  - Blügel, Stefan
AU  - Morgenstern, Markus
AU  - Schneider, Claus M.
AU  - Grützmacher, Detlev
TI  - Realization of a vertical topological p–n junction in epitaxial Sb$_{2}$Te$_{3}$/Bi$_{2}$Te$_{3}$ heterostructures
JO  - Nature Communications
VL  - 6
SN  - 2041-1723
CY  - London
PB  - Nature Publishing Group
M1  - FZJ-2015-06632
SP  - 8816
PY  - 2015
AB  - Three-dimensional (3D) topological insulators are a new state of quantum matter, which exhibits both a bulk band structure with an insulating energy gap as well as metallic spin-polarized Dirac fermion states when interfaced with a topologically trivial material. There have been various attempts to tune the Dirac point to a desired energetic position for exploring its unusual quantum properties. Here we show a direct experimental proof by angle-resolved photoemission of the realization of a vertical topological p–n junction made of a heterostructure of two different binary 3D TI materials Bi2Te3 and Sb2Te3 epitaxially grown on Si(111). We demonstrate that the chemical potential is tunable by about 200 meV when decreasing the upper Sb2Te3 layer thickness from 25 to 6 quintuple layers without applying any external bias. These results make it realistic to observe the topological exciton condensate and pave the way for exploring other exotic quantum phenomena in the near future.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000366295500002
C6  - pmid:26572278
DO  - DOI:10.1038/ncomms9816
UR  - https://juser.fz-juelich.de/record/276159
ER  -