Seminars Archive

Narrow photoluminescence and Raman peaks of epitaxial MoS₂ on graphene/Ir(111)

Abstract
We report the observation of photoluminescence (PL) with a narrow 18 meV peak width from MoS₂ grown via molecular beam epitaxy on a graphene/Ir(111) substrate. The absence of PL quenching by the metallic substrate is explained by a weak graphene-MoS₂ interaction. We use angle-resolved photoemission spectroscopy (ARPES) and temperature-dependent Raman spectroscopy to highlight the weak substrate interaction of the MoS₂ layer, finding no hybridization of the electronic states of MoS₂ and graphene as well as a different thermal expansion of both layers. MoS₂ grown via molecular beam epitaxy on graphene is thus an important system for optoelectronic applications which allows for a macroscopically homogeneous large area growth with controlled properties.