| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2018) | |
| Nanomaterials | Monday Sessions |
| Session NM-MoM |
| Session: | Nanocharacterization |
| Presenter: | Adam Schwartzberg, Lawrence Berkeley National Laboratory |
| Authors: | A.M. Schwartzberg, Lawrence Berkeley National Laboratory C. Kastl, Lawrence Berkeley National Laboratory S. Aloni, Lawrence Berkeley National Laboratory A. Weber-Bargioni, Lawrence Berkeley National Laboratory C.T. Chen, Lawrence Berkeley National Laboratory |
| Correspondent: | Click to Email |
Two-dimensional materials with engineered composition and structure will provide designer materials beyond conventional semiconductors. However, the potentials of defect engineering remain largely untapped, because it hinges on a precise understanding of electronic structure and excitonic properties, which are yet not predictable by theory alone. Here, we introduce correlative, nanoscale photoemission spectroscopy to visualize how the local introduction of defects modifies electronic and excitonic properties of two-dimensional materials at the nanoscale. As a model system, we study chemical vapor deposition grown monolayer WS2, a prototypical, direct gap, two-dimensional semiconductor. By cross-correlating nanoscale angle resolved photoemission spectroscopy, core level spectroscopy and photoluminescence, we unravel how local variations in defect density influence electronic structure, lateral band alignment and excitonic phenomena in synthetic WS2 monolayers. Our results not only provide a unified picture of nanoscale heterogeneity, but they also open up the possibility to precisely understand and tailor lateral heterointerfaces in such two-dimensional materials.