A5003472926- Force Microscopy Techniques and Applications
- Molecular Junctions and Nanostructures
- Mechanical and Optical Resonators
- Topological Materials and Phenomena
- Advanced Materials Characterization Techniques
- Quantum and electron transport phenomena
- Surface and Thin Film Phenomena
- Graphene research and applications
- Cold Atom Physics and Bose-Einstein Condensates
- Physics of Superconductivity and Magnetism
- Surface Chemistry and Catalysis
- Atomic and Molecular Physics
- Quantum, superfluid, helium dynamics
- 2D Materials and Applications
- Advanced Chemical Physics Studies
- Photorefractive and Nonlinear Optics
- Diamond and Carbon-based Materials Research
- Electronic and Structural Properties of Oxides
- Semiconductor materials and interfaces
University of Regensburg
2015-2021
Georgetown University
2020
University of Basel
2020
Seoul National University
2020
Theiss Research
2020
University of Maryland, College Park
2020
Material Measurement Laboratory
2020
Physical Measurement Laboratory
2020
National Institute of Standards and Technology
2020
Imaging a chemisorption process At low temperatures, molecule may adsorb to surface only through weak forces (physisorption), and upon heating overcoming an energetic barrier does it form strong covalent bond (chemisorption). Huber et al. imaged this transition for atomic force microscopy tip terminating in carbon monoxide molecule. Although the oxygen atom of is normally considered act like rare gas atom, interacting van der Waals interactions, at short distances directly above metal...
Small metal clusters have been investigated for decades due to their beneficial catalytic activity. It was found that edges are most reactive and the number of events increases with cluster's size. However, a direct measurement chemical reactivity individual atoms within has not reported yet. We combine high-resolution capability CO-terminated tips in scanning probe microscopy ability binding forces on single Fe study atom-by-atom assembled from 1 15 atomic scale. find flat does depend...
The quantum Hall (QH) effect, a topologically non-trivial phase, expanded and brought into focus the concept of topological order in physics. protected edge states are crucial importance to QH effect but have been measured with limited success. graphene take on an even richer role as is distinguished by its four-fold degenerate zero energy Landau level (zLL), where symmetry broken electron interactions top lattice-scale potentials has eluded spatial measurements. In this report, we map...
Research in new quantum materials requires multi-mode measurements spanning length scales, correlations of atomic-scale variables with a macroscopic function, and spectroscopic energy resolution obtainable only at millikelvin temperatures, typically dilution refrigerator. In this article, we describe instrument achieving μeV tunneling in-operando measurement capabilities scanning microscopy, atomic force magnetotransport inside refrigerator operating 10 mK. We the system detail including...
Through a combination of experimental techniques we show that the topmost layer topological insulator TlBiSe2 as prepared by cleavage is formed irregularly shaped Tl islands at cryogenic temperatures and mobile atoms room temperature. No trivial surface states are observed in photoemission low temperatures, which suggests these cannot be regarded clear termination. The state is, however, clearly resolved experiments. This interpreted direct evidence its self-protection shows robust nature...
We explored the bonding properties of quantum corral (a circle 48 iron atoms placed on a copper surface) reported by Crommie et al. in 1993, along with variants, as an artificial atom using atomic force microscope (AFM). The original geometry confines 102 electrons to 28 discrete energy states, and we found that these states can form bond front AFM about 5 millielectron volts. measured forces are 1/1000 typical atomically resolved AFM. confined showed covalent attraction metal tips Pauli...
CO-terminated tips currently provide the best spatial resolution obtainable in atomic force microscopy. Due to their chemical inertness, they allow probe interactions dominated by Pauli repulsion. The small size and inertness of oxygen front atom yields unprecedented organic molecules, metal clusters surfaces. We study capability laterally manipulate single iron adatoms on Cu(111) surface with combined scanning tunneling microscopy at 7\,K. Furthermore, we find that even a slight asymmetry...