Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 100: Topological Insulators II
O 100.6: Talk
Friday, March 11, 2016, 11:15–11:30, H15
Structural Study of Weak Topological Insulator Bi1Te1 Films on Si(111) grown by Molecular Beam Epitaxy — •Martin Lanius1, Markus Eschbach1, Ewa Mlynczak1, Jens Kellner2, Pika Gospodaric1, Chengwang Niu1, Elmar Neumann1, Martina Luysberg3, Gregor Mussler1, Lukasz Plucinski1, Gustav Bihlmayer1, Stefan Blügel1, Markus Morgenstern2, Claus Michael Schneider1, and Detlev Grützmacher1 — 1Peter Grünberg Institut, Forschungszentrum Jülich, Germany — 2II. Institute of Physics B and JARA-FIT, RWTH Aachen University, Aachen, Germany — 3Ernst Ruska-Centre for Microscopy and Spectroskopy with Electrons, Forschungszentrum Jülich, Germany
We have studied the nucleation, growth process and structural composition of the weak topological insulator Bi1Te1 on Si(111) substrates by STM and STEM. Bi1Te1 is a superlattice of predicted 2D topological insulating materials, one bilayer Bi and two Bi2Te3 quintuple layers per unit cell. The van der Waals growth mode of Bi1Te1 shows smooth surfaces and a supressed twin domain density. The thin films from several nanometers thickness down to the nucleation regime have been grown by molecular beam epitaxy. STEM measurements of the grown films reveal a high crystalline perfection. Simulations and ARPES measurements show 2D surface states originating from spin-orbit coupling, depending in their structure on the surface termination. Furthermore we will demonstrate the ability to grow n-p heterostructures of n-doped Bi1Te1 with the p-doped strong TI Sb2Te3.