Regensburg 2019 – wissenschaftliches Programm
MA 4.2: Vortrag
Montag, 1. April 2019, 09:45–10:00, H52
Laser induced DC photocurrents in 3D topological insulators Hall bar and nanowire devices — •Nina Meyer1, Thomas Schumann1, Eva Schmoranzerová2, Kevin Geishendorf3, Gregor Mussler4, Jakob Walowski1, Petr Nemec2, Andy Thomas3, Kornelius Nielsch3, Detlev Grützmacher4, and Markus Münzenberg1 — 1Institute of Physics, University of Greifswald, Greifswald, Germany — 2Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic — 3IFW Dresden, Institute for Metallic Materials, Dresden, Germany — 4Inst. for Semiconductor Nanoelectronics, PGI-9, Forschungszentrum Jülich, Germany
It has been demonstrated experimentally that spin-polarized currents can be generated by illuminating a topological insulator (TI) with circularly polarized light . In this talk, we will sum up our results for (Bi, Sb)2Te3 thin films Hall bar structures and Bi2Se3 core-shell nanowires. During the photocurrent measurements, the laser light polarisation is changed at every laser spot position. Due to the polarisation dependence, the different contribution to the photocurrent are separated and displayed as spatially resolved 2D maps. For the Hall bar structure a lateral accumulation of spin polarization at the TIs edges due to the spin Nernst effect is found . For the nanowires, the interaction between nanowire and Au contact due to the Schotky effect and a constant spin polarized current far off the contacts is found.
J.W. McIver et al., Nature Nanotechnology 7, 96-100 (2012)
T. Schumann et al., arXiv:1810.12799 (submitted)