Growth and electronic structure of single-layered transition metal dichalcogenides
MPSD Seminar
- Date: Jul 28, 2016
- Time: 11:00 AM - 12:00 PM (Local Time Germany)
- Speaker: Maciej Dendzik
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University, Denmark
- Location: CFEL (Bldg. 99)
- Room: Seminar Room IV, O1.111
- Host: Isabella Gierz
The discovery of graphene established the possibility of obtaining stable two-dimensional solids, and it was soon realized that layered materials other than graphite can be used as bulk parents for novel two-dimensional materials. Among them, layered transition metal dichalcogenides have attracted considerable attention due to interesting physical properties and potential for electronics applications. While most of the research focused on mechanically exfoliated specimens, many proposed approaches to characterizing these materials, as well as potential applications, require large-area and high-quality samples. These can be achieved by epitaxial growth methods developed in our group.
During this talk several systems of single-layered transition metal
dichalcogenides (MoS2, WS2, TaS2) epitaxially-grown on Au(111) and
graphene/SiC will be discussed in the context of electronic structure
measured with angle-resolved photoemission spectroscopy and
scanning-tunneling microscopy. Experimental results will be compared
with density functional theory calculations which include also the
contribution of a substrate. The effect of herringbone reconstruction on
the electronic structure of the Au(111) surface will be analyzed. In
addition, it will be shown how the localized character of the orbitals
can lead to unexpected spin-polarization in non-magnetic centrosymmetric
bulk WSe2 crystals.