| AVS 64th International Symposium & Exhibition | |
| 2D Materials Focus Topic | Tuesday Sessions |
| Session 2D+BI+MN+SS-TuA |
| Session: | Surface Chemistry, Functionalization, Bio and Sensor Applications |
| Presenter: | Sara Barja, Materials Physics Center, San Sebastián, Spain |
| Authors: | S. Barja, Materials Physics Center, San Sebastián, Spain S. Wickenburg, Molecular Foundry, Lawrence Berkeley Lab Z.-F. Liu, Molecular Foundry, Lawrence Berkeley Lab Y. Zhang, Molecular Foundry, Lawrence Berkeley Lab A. Pulkin, Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland S. Refaely-Abramson, Molecular Foundry, Lawrence Berkeley Lab B. Schuler, Molecular Foundry, Lawrence Berkeley Lab H. Ryu, Lawrence Berkeley National Laboratory D. Qiu, University of California at Berkeley M. M. Ugeda, CIC nanoGUNE, Spain Z.-X. Shen, Stanford Institute of Materials and Energy Sciences S.-K. Mo, Lawrence Berkeley National Laboratory M.B. Salmeron, Lawrence Berkeley National Laboratory M.F. Crommie, University of California at Berkeley D.F. Ogletree, Molecular Foundry, Lawrence Berkeley Lab O.V. Yazyev, Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland J.B. Neaton, Molecular Foundry, Lawrence Berkeley Lab A. Weber-Bargioni, Molecular Foundry, Lawrence Berkeley Lab |
| Correspondent: | Click to Email |
Properties of two-dimensional transition metal dichalcogenides are highly sensitive to the presence of defects in the crystal structure. A detailed understanding of the defect electronic structure may lead not only to the control of the material’s properties through defect engineering towards a particular device application, but also may lead the emergence of novel physico-chemical functionalities. We show how linear mirror twin boundaries and individual atomic defects in single-layer MoSe2 alter the electronic structure of the pristine semiconductor. Such linear and point defects tend to be highly localized in the plane, which imposes the need of experimental and theoretical characterization of the defects at the atomic level. Using non-contact atomic force microscopy and scanning tunneling spectroscopy, we directly correlate the morphology and electronic properties of structural defects in MoSe2 at the defect-length scale. We provide direct evidence for the existence of isolated, one-dimensional charge density waves at mirror twin boundaries in single-layer MoSe2. We also determine the local density of states of Se vacancies in monolayer MoSe2 and discuss the correlation to density functional theory calculations, studying the role of the GW approximation to reproduce the energetics of the valence and conduction band as measured in the experimental dI/dV spectra.