Dresden 2017 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

DS: Fachverband Dünne Schichten

DS 27: 2D Materials beyond Graphene (jointly with O)

DS 27.5: Poster

Dienstag, 21. März 2017, 18:30–20:30, P2-EG

Low Temperature Scanning Tunneling Spectroscopy on MoS₂ nanoflakes on Au(111) — •Daniela Dombrowski^1,2 and Carsten Busse^1,2 — ¹II. Physikalisches Institut, Universität zu Köln — ²Institut für Materialphysik, Westfälische Wilhelms-Universität Münster

We perform low temperature scanning tunneling spectroscopy at 5 K of MoS₂ nanoflakes grown on Au(111) by a combination of physical and chemical vapour deposition. We find a band gap of approx. 1.9 eV and pronounced peaks, originating from the MoS₂ bands. The Shockley-surface state at 0.5 eV is present on the bare gold surface, but absent below the MoS₂ islands.

Furthermore, we take advantage of the spatial resolution of scanning tunneling spectroscopy to measure the influence of the moiré superstructure arising from the lattice mismatch between the MoS₂ layer and the underlying gold substrate. We observe a significant shift of the valence band edge, whereas the conduction band remains almost unchanged, hence leading to a variation of the gap energy induced by the moiré pattern.

Finally, we find a new state right above the valence band, which is associated with the edge of the MoS₂ flakes.