Electronic band dispersion determination in azimuthally disordered transition-metal dichalcogenide monolayers

• Published in: Communications physics 2019-06, Vol.2 (1), Article 68
• Main Authors: Park, S., Schultz, T., Han, A., Aljarb, A., Xu, X., Beyer, P., Opitz, A., Ovsyannikov, R., Li, L.-J., Meissner, M., Yamaguchi, T., Kera, S., Amsalem, P., Koch, N.
• Format: Article
• Language: English
• Subjects: 639/301/357; 639/766/119; Physics; Physics and Astronomy
• ISSN: 2399-3650; 2399-3650
• DOI: 10.1038/s42005-019-0166-0

Generally, the lack of long-range order in materials prevents from experimentally addressing their electronic band dispersion by angle-resolved photoelectron spectroscopy (ARPES), limiting such assessment to single crystalline samples. Here we demonstrate that the ARPES spectra of azimuthally disordered transition metal dichalcogenide (TMDC) monolayers with 2 H phase are dominated by their band dispersion along the two high symmetry directions Γ-K and Γ-M. We exemplify this by analyzing the ARPES spectra of four prototypical TMDCs within a mathematical framework, which allows to consistently explain the reported observations. A robust base for investigating TMDC monolayers significantly beyond single crystal samples is thus established. The complex nature of polycrystalline materials mean that characteristics such as their electronic band structure can be more challenging to interpret than their single crystal counterparts. Here, the authors present a framework based on angle-resolved photoemission spectroscopy to reveal the band dispersions for azimuthally disordered transition metal dichalcogenide polycrystalline monolayers.