Dresden 2014 – wissenschaftliches Programm
O 35.2: Vortrag
Dienstag, 1. April 2014, 14:15–14:30, HSZ 304
Finite width effect on weak antilocalization in MBE grown Bi2Te3 thin films — •Christian Weyrich1,2, Tobias Merzenich1,2, Igor E. Batov3, Gregor Mussler1,2, Jörn Kampmeier1,2, Jürgen Schubert1, Thomas Schäpers1,2, and Detlev Grützmacher1,2 — 1Peter Grünberg Institute (PGI-9) and JARA-Fundamentals of Future Information Technology, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany — 2Virtual Institute for Topological Insulators (VITI), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany — 3Institute of Solid State Physics, Russian Academy of Sciences, Chernogolovka, 142432, Moscow Distr., Russia
The weak antilocalization effect is measured in Bi2Te3 layers under various tilt angles of the magnetic field with respect to the layer surface. The investigated Bi2Te3 layer was prepared by molecular beam epitaxy. For a magnetic field oriented perpendicularly to the layer the weak antilocalization effect at different temperatures can be well-fitted by the Hikami-Larkin-Nagaoka model. From the fit a phase coherence length of about 200 nm is obtained at a temperature of 2 K. A clear signature of weak antilocalization is also observed when the magnetic field is oriented parallel to the Bi2Te3 layer. This effect is compared to classical models as well as a recently developed theory, which takes into account the finite penetration depth of the surface or interface states into the bulk.