Regensburg 2016 – wissenschaftliches Programm
MM 15.15: Poster
Montag, 7. März 2016, 18:00–20:00, Poster B3
Theoretical investigation of BiTeX (X=Cl,Br,I): Crystal structure and optical conductivity — •René Wirnata1, Sebastian Schwalbe1, Giulio A.H. Schober2, Jens Kortus1, and Ronald Starke1 — 1TU Freiberg, Institute for Theoretical Physics, Germany — 2University of Heidelberg, Institute for Theoretical Physics, Germany
Recently, the group of bismuth tellurohalides (BiTeX, X=Cl,Br,I) has been discovered to show a giant bulk Rashba splitting  that can be used e.g. in spintronics applications or magneto-optical devices [2,3]. Starting from X-ray data , we have constructed mono and double layer models of the experimental crystal systems. Using density functional theory, we discover a graphene/graphite-like band-crossing, which can also be observed in the low-frequency region of the optical response tensor. This may provide a new method for structural characterization by performing optical conductivity measurements.
Furthermore, this materials class shows a layered electron localization around the X and Te atoms, which manifests itself in the form of an increased conductivity in this plane.
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