Phase-coherent transport in selectively grown topological insulator nanodots. (30th November 2018)

• Record Type: Journal Article
• Authors: Weyrich, Christian; Lanius, Martin; Schüffelgen, Peter; Rosenbach, Daniel; Mussler, Gregor; Bunte, Stephany; Trellenkamp, Stefan; Grützmacher, Detlev; Schäpers, Thomas
• Is Part Of: Nanotechnology. Volume 30:Number 5(2019)
• Publication Date: 2018-11-30
• Subjects: topological insulators -- magnetotransport -- selective area growth -- molecular beam epitaxy -- phase-coherent transport; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/1361-6528/aaee5f
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: Oxidized Si(111) substrates were pre-structured by electron beam lithography and used as a substrate for the selective growth of three-dimensional topological insulators (TI) by molecular beam epitaxy. The patterned holes were filled up by the TI, i.e. Sb2 Te3 and Bi2 Te3, to form nanodots. Scanning electron microscopy and focused ion beam cross-sectioning was utilized to determine the morphology and depth profile of the nanodots. The magnetotransport measurements revealed universal conductance fluctuations originating from electron interference in phase-coherent loops. We find that these loops are oriented preferentially within the quintuple layers of the TI with only a small perpendicular contribution. Furthermore, we found clear indications of an conductivity anisotropy between different crystal orientations.