STM on Layered Materials

Topographic and Energetic Heterogeneity Studies of Oxidized Graphite Surface by Scanning Tunneling Microscopy/Spectroscopy and Photoelectron Spectroscopy

“…9b), the characteristic features for a pure graphite surface can be distinguished at around 1.7 eV and 2.2 eV and are attributed to the specific points of the Brillouin zone Q2u., and Q 2 g , r e s p e c t i v e l y (graphite band structure after Painter and Ellis [11]; symmetry designations based on the modified version by Willis and Fitton [12]). Another structure at 2.7-3 eV, denoted as ES, is associated with the extrinsic surface state [10]. On the whole, these results are in good agreement with the experimental investigations by Reihl et al [13] and by Fusch and Tosatti [14], and with the theoretical researches by Selloni et al [15].…”

“…Consequently, the Bloch waves of graphite with the energy around the Fermi level have a larger amplitude around the B site than around the A site. The type B atoms contribute in a larger extent to tunneling current than the type A atoms, and a tunneling microscope detects only the type B atoms, whereas the type A atoms remain almost invisible [10]. It confirms that STM does not show an atomic structure of the surface in crystallographic sense, but rather an atomic structure of the surface which is strongly affected by the local electronic density of states.…”

Graphite Electrodes Immersed in Nonaqueous Li+ Electrolytes Studied with a Combined Ultrahigh Vacuum–Electrochemistry Approach

“…These observations are consistent with the presence of sp 2 hybridized carbon. − Aside from the C 1s features, no other features are present in the wide spectrum, while the negligible O 1s spectrum (Figure S2a) indicates that the pristine surface is clean and without functional groups. In line with XPS are the STM images in Figure d (larger-scale images in Figure S2d), which show that the pristine HOPG contains atomically flat terraces that are hundreds of nanometers in size, while the step heights are close to the expected 0.335 nm . Observation at a higher resolution shows the atomically resolved three-fold hexagonal pattern of graphite (Figure d inset).…”

Kondo effect in graphene with Rashba spin-orbit coupling

“…Single-or few-layer structures facilitate control by chemical and/or electrical means, as well as direct access to electronic features using local probes such as scanning tunneling microscopy. 3 Coupling between orbital and spin degrees of freedom has noticeable effects on the properties of many singlelayer materials. Spin-orbit interaction (SOI) can come into play either in its intrinsic form arising from the presence of constituent atoms with high atomic number, for instance in transition-metal dichalcogenides, or in extrinsic form due to the breaking of the electron spin degeneracy through spatial-inversion asymmetry arising from a substrate or an external electric field.…”