The Dr. Lian Li Research group has moved to the Department of Physics and Astronomy at West Virginia University in Morgantown, WV.
We research structure and property relationships of condensed matter at the atomic scale. Our current focus is graphene nanostructures, topological insulators, and emergent functionalities at the epitaxial interfaces of correlated and spin-orbit materials. The studies involve material growth using molecular beam epitaxy and chemical vapor deposition, atomic-scale characterization using scanning tunneling microscopy/spectroscopy, and x-ray absorption spectroscopy/magnetic circular dichroism. We work closely with Prof. Michael Weinert on first principles calculations of material properties.
Nanoribbons are model systems for studying nanoscale effects in graphene. For ribbons with zigzag edges, tunable bandgaps have been predicted due to coupling of spin-polarized edge states, which have yet to be systematically demonstrated experimentally. The Lian Li group synthesized zigzag nanoribbons using Fe nanoparticle-assisted hydrogen etching of epitaxial graphene/SiC(0001) in ultrahigh vacuum. Two gaps in their local density of states were observed by scanning tunnelling spectroscopy. As discussed in a recent Nature Communications article: the results of these experiments provide direct experimental confirmation of electron–electron interactions in gap opening in zigzag nanoribbons, and reveal a critical width of 3 nm for its onset.