Berlin 2018 – scientific programme

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TT: Fachverband Tiefe Temperaturen

TT 28: Poster Session: Topological Topics

TT 28.16: Poster

Monday, March 12, 2018, 15:00–19:00, Poster B

Fractional quantum Hall phenomenology in mosaic-like conductors — Ferdinand Kisslinger¹, •Dennis Rienmüller¹, Erik Kampert², and Heiko B. Weber¹ — ¹FAU Erlangen-Nürnberg, Lehrstuhl für angewandte Physik — ²High Magnetic Field Laboratory, Helmholtz-Zentrum Dresden-Rossendorf

In the early days of graphene research, fractional values of e²/h in the two-terminal conductance were interpreted as heralding FQHE in graphene [1],[2]. Since then, a variety of detailed investigations of FQHE states in monolayer [3]-[5] were reported.
In this work, another approach was made by utilizing a simple route to generate magnetotransport data that share essential signatures with fractional quantum Hall effect. Ingredients to the generating model are, on the one hand, conducting tiles with integer quantum Hall effect as well as metallic linkers, and, on the other hand, Kirchhoff’s laws. When connecting few identical tiles in a mosaic, fractional steps occur in the conductance values. Richer spectra representing several fractions occur when the tiles are parametrically varied. Parts of the simulation data are supported with purposefully designed graphene mosaics in high magnetic fields. The model can, however, not explain substructure within the last Landau level. The findings emphasize that the occurrence of FQH phenomena does not necessarily indicate interaction-driven physics.
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