Protected hole valley states in single-layer Molybdenum disulfide

We present an angle-resolved photoemission spectroscopy study of single-layer
molybdenum disulfide where interaction with a supporting highly ordered pyrolytic graphite substrate was controlled by temperature change, consistent with related modifications in the layer-substrate distance. The impact of interface potential landscape changes on the electronic properties and charge dynamics on the
molybdenum disulfide layer was evaluated by valence-band dispersion and photoemission line-shape analysis. Our results indicate that the hole states at the
K-valley point are essentially unaffected by interface potential, reflecting the strong-in plane localization of the electronic wave function.