title: Vacuum ultraviolet excitation luminescence spectroscopy of few-layered MoS2.
abstract: We report on vacuum ultraviolet (VUV) excited photoluminescence (PL) spectra emitted from a chemical vapor deposited MoS2 few-layered film. The excitation spectrum was recorded by monitoring intensities of PL spectra at ~1.9 eV. A strong wide excitation band peaking at 7 eV was found in the excitation. The PL excitation band is most intensive at liquid helium temperature and completely quenched at 100 K. Through first-principles calculations of photoabsorption in MoS2, the excitation was explicated and attributed to transitions of electrons from p- and d- type states in the valence band to the d- and p-type states in the conduction band. The obtained photon-in/photon-out results clarify the excitation and emission behavior of the low dimensional MoS2 when interacting with the VUV light sources.
authors.affiliation: Research Centre for Molecular Materials, PO Box 3000, FIN- 90014, University of Oulu, Finland.
authors.forename: V
authors.initials: V
authors.lastname: Pankratov
authors.forename: J
authors.initials: J
authors.lastname: Hoszowska
authors.forename: J-Cl
authors.initials: JC
authors.lastname: Dousse
authors.forename: M
authors.initials: M
authors.lastname: Huttula
authors.forename: A
authors.initials: A
authors.lastname: Kis
authors.forename: D
authors.initials: D
authors.lastname: Krasnozhon
authors.forename: M
authors.initials: M
authors.lastname: Zhang
authors.forename: W
authors.initials: W
authors.lastname: Cao