A5031956896- Graphene research and applications
- Molecular Junctions and Nanostructures
- Silicon Carbide Semiconductor Technologies
- Semiconductor materials and devices
- Quantum and electron transport phenomena
- Advancements in Semiconductor Devices and Circuit Design
- Diamond and Carbon-based Materials Research
- Force Microscopy Techniques and Applications
- Laser-Matter Interactions and Applications
- Semiconductor materials and interfaces
- Silicon and Solar Cell Technologies
- Nanowire Synthesis and Applications
- Surface and Thin Film Phenomena
- Spectroscopy and Quantum Chemical Studies
- Crystallization and Solubility Studies
- Carbon Nanotubes in Composites
- Integrated Circuits and Semiconductor Failure Analysis
- X-ray Diffraction in Crystallography
- Thin-Film Transistor Technologies
- Copper Interconnects and Reliability
- 2D Materials and Applications
- Physics of Superconductivity and Magnetism
- Graphene and Nanomaterials Applications
- Semiconductor Quantum Structures and Devices
- Terahertz technology and applications
Friedrich-Alexander-Universität Erlangen-Nürnberg
2016-2025
University of Bonn
2023-2025
Infineon Technologies (Austria)
2023
Siemens (Austria)
2023
Bayer (Germany)
2021
Institut für Technische und Angewandte Physik (Germany)
2017
Helmholtz-Zentrum Dresden-Rossendorf
2012
University of California, Santa Barbara
2012
University of British Columbia
2008-2009
University of Cologne
1953-2009
We investigate electronic transport through two types of conjugated molecules. Mechanically controlled break junctions are used to couple thiol end groups single molecules gold electrodes. Current-voltage characteristics ( IVs) the metal-molecule-metal system observed. These IVs reproduce spatial symmetry with respect direction current flow. hereby unambiguously detect an intrinsic property molecule and able distinguish influence both contact metal electrodes on properties compound system.
We have designed and synthesized a molecular rod that consists of two weakly coupled electronic π -systems with mutually shifted energy levels. The asymmetry thus implied manifests itself in current–voltage characteristic pronounced dependence on the sign bias voltage, which makes molecule prototype for diode. individual molecules were immobilized by sulfur–gold bonds between both electrodes mechanically controlled break junction, their transport properties been investigated. results indeed...
For the first time a new device concept for high voltage power devices has been realized in silicon. Our 600 V-COOLMOS/sup TM/ reaches an area specific on-resistance of typically 3.5 /spl Omega//spl middot/mm/sup 2/. technology thus offers shrink factor 5 versus actual state art MOSFETs. The is based on charge compensation drift region transistor. We increase doping vertical roughly by one order magnitude and counterbalance this additional implementation fine structured columns opposite...
Epitaxial growth of graphene on SiC surfaces by solid state graphitization is a promising route for future development based electronics. In the present work, we have studied morphology, atomic scale structure, and electronic structure thin films few-layer (FLG) SiC(0001) scanning tunneling microscopy spectroscopy (STS). We show that quantitative evaluation roughness induced interface tool determining layer thickness FLG. interpret dependent spectra, which can serve as an additional...
We have measured the non-local resistance of aluminum-iron spin-valve structures fabricated by e-beam lithography and shadow evaporation. The sample geometry consists an aluminum bar with two or more ferromagnetic wires forming point contacts to at varying distances from each other. In normal state aluminum, we observe a signal which allows us control relative orientation magnetizations contacts. superconducting state, low temperatures excitation voltages well below gap, spin-dependent...
The electronic resistance of an electrode-molecule-electrode device strongly depends on the relative position anchor group in molecular structure. rod, immobilized through two sulfur groups meta a pair electrodes (see picture), displays considerably increased compared to rod with para position.
A simple and scalable scheme based on alternating current (ac-) dielectrophoresis is used for the simultaneous site-selective deposition of single bundles single-walled carbon nanotubes (SWNTs) onto a large number contacts requiring only one bond wire. This allows transport measurements that show deposited contain at least metallic SWNT dominating transport. With high-voltage pulses, are transformed into Schottky-barrier-type field-effect transistors with p-type, ambipolar, or n-type...
We analyze quantum interference and decoherence effects in single-molecule junctions both experimentally theoretically by means of the mechanically controlled break junction technique density-functional theory. consider case where is provided overlapping quasidegenerate states. Decoherence mechanisms arising from electronic-vibrational coupling strongly affect electrical current flowing through a contact can be temperature variation. Our findings underline universal relevance vibrations for...
We present a statistical approach that combines comprehensive current-voltage data acquisition during the controlled manipulation of molecular junction with subsequent analysis. Thereby most probable transport characteristics can be determined. The excellent sensitivity this impartial to even subnanometer-long molecules is illustrated by benzene-1,4-dithiol and 4,4"-bis(acetylthiol)-2,2',5',2"-tetramethyl-[1,1';4',1"] terphenyl results.
We report on an investigation of quasi-free-standing graphene 6H-SiC(0001) which was prepared by intercalation hydrogen under the buffer layer. Using infrared absorption spectroscopy we prove that SiC(0001) surface is saturated with hydrogen. Raman spectra demonstrate conversion layer into exhibits a slight tensile strain and short range defects. The layers are hole doped (p = 5.0-6.5 x 10^12 cm^(-2)) carrier mobility 3,100 cm^2/Vs at room temperature. Compared to strongly reduced...
We investigate the transport properties of high-quality single-layer graphene, epitaxially grown on a 6H-SiC(0001) substrate. have measured properties, in particular charge-carrier density, mobility, conductivity, and magnetoconductance large samples as well submicrometer-sized Hall bars which are entirely lying atomically flat substrate terraces. The results display high mobilities, independent sample size. temperature dependence conductance indicates rather strong coupling to SiC An...
Long carrier lifetimes and diffusion lengths form the basis for successful application of organic-inorganic perovskite (CH$_3$NH$_3$)PbI$_3$ in solar cells lasers. The mechanism behind long is still not completely understood. Spin-split bands a resulting indirect band gap have been proposed by theory. Using near band-gap left-handed right-handed circularly polarized light we induce photocurrents opposite directions single-crystal device at low temperature ($4~\mathrm{K}$). phenomenom known...
Graphene is an outstanding electronic material, predicted to have a role in post-silicon electronics. However, owing the absence of bandgap, graphene switching devices with high on/off ratio are still lacking. Here search for comprehensive concept wafer-scale electronics, we present monolithic transistor that uses entire material system epitaxial on silicon carbide (0001). This consists layer its vanishing energy gap, underlying semiconductor and their common interface. The...
We investigate coherent electron dynamics in graphene, interacting with the electric field waveform of two orthogonally polarized, few-cycle laser pulses. Recently, we demonstrated that linearly polarized driving pulses lead to sub-optical-cycle Landau-Zener quantum path interference by virtue combination intraband motion and interband transition [Higuchi et al., Nature 550, 224 (2017)NATUAS0028-083610.1038/nature23900]. Here introduce a pulsed control beam, pulses, observe ensuing dynamics....
Targeted protein degradation (TPD) represents a promising alternative to conventional occupancy-driven inhibition. Despite the existence of more than 600 E3 ligases in human proteome, so far only few have been utilized for TPD histone deacetylases (HDACs), which represent important epigenetic anticancer drug targets. In this study, we disclose first-in-class Fem-1 homologue B (FEM1B)-recruiting HDAC degraders. A set 12 proteolysis targeting chimeras (PROTACs) was synthesized using...
A further component for molecular electronics: single molecule insulator is realized by immobilizing a platinum(II) complex between two gold electrodes (see picture). The current/voltage characteristics of the setup shows typical behavior an with tunnel barrier height 2.5 eV.
We investigate the magnetotransport in large area graphene Hall bars epitaxially grown on silicon carbide. In intermediate field regime between weak localization and Landau quantization observed temperature-dependent parabolic magnetoresistivity (MR) is a manifestation of electron-electron interaction (EEI). can consistently describe data with model for diffusive (magneto)transport that also includes magnetic-field dependent effects originating from ballistic time scales. find an excellent...
On the way to ultraflat single-molecule junctions with transparent electrodes, we present a fabrication scheme based on epitaxial graphene nanoelectrodes. As suitable molecule, identified molecular wire fullerene anchor groups. With these two components, stable electrical characteristics could be recorded. Electrical measurements show that and gold electrodes display striking agreement. This motivated hypothesis differential conductance spectra are rather insensitive electrode material. It...