A5005632579- Graphene research and applications
- Molecular Junctions and Nanostructures
- Semiconductor materials and devices
- Electronic and Structural Properties of Oxides
- 2D Materials and Applications
- Diamond and Carbon-based Materials Research
- MXene and MAX Phase Materials
- Ferroelectric and Piezoelectric Materials
- Semiconductor materials and interfaces
- Boron and Carbon Nanomaterials Research
- Theoretical and Computational Physics
- Micro and Nano Robotics
- Surface and Thin Film Phenomena
- Characterization and Applications of Magnetic Nanoparticles
- Magnetic and transport properties of perovskites and related materials
- Carbon Nanotubes in Composites
- Organic Electronics and Photovoltaics
- Arctic and Antarctic ice dynamics
- Ion-surface interactions and analysis
- Nanowire Synthesis and Applications
- Conducting polymers and applications
- Quantum and electron transport phenomena
- Perovskite Materials and Applications
- Advancements in Semiconductor Devices and Circuit Design
- Metal and Thin Film Mechanics
Chemnitz University of Technology
2016-2025
Rice University
2022
Superconducting and other Innovative Materials and Devices Institute
2022
University of Genoa
2022
Technische Universität Dresden
2008-2021
Helmholtz-Zentrum Dresden-Rossendorf
2011-2020
Center for Systems Biology Dresden
2018-2019
Tohoku University
2010
University of Surrey
2010
Fraunhofer Institute for Material and Beam Technology
2009
We present a first-principles density functional study of the structural, electronic and magnetic properties ferroelectric domain walls in multiferroic BiFeO3. find that which rotations oxygen octahedra do not change their phase when polarization reorients are most favorable, these 109 degree wall centered around BiO plane has lowest energy. The 180 have significant component perpendicular to wall; corresponding step electrostatic potential is consistent with recent report electrical...
[3]-Radialene-based dopant CN6-CP studied herein, with its reduction potential of +0.8 versus Fc/Fc+ and the lowest unoccupied molecular orbital level −5.87 eV, is strongest p-dopant reported in open literature, so far. The efficient p-doping donor–acceptor dithienyl-diketopyrrolopyrrole-based copolymer having highest −5.49 eV achieved. doped films exhibit electrical conductivities up to 70 S cm−1. As a service our authors readers, this journal provides supporting information supplied by...
Using {\em ab initio} density functional theory calculations, we characterize changes in the electronic structure of MoS$_{2}$ monolayers introduced by missing or additional adsorbed sulfur atoms. We furthermore identify chemical and function substances that have been reported to reduce adverse effect vacancies quenching photoluminescence reducing conductance. find thiol-group containing molecules at vacancy sites may re-insert In presence atoms, thiols form disulfides on surface mitigate defects.
Herein we present a molecular doping of high mobility diketopyrrolopyrrole–dithienylthieno[3,2-b]thiophene donor–acceptor copolymer poly[3,6-(dithiophene-2-yl)-2,5-di(6-dodecyloctadecyl)pyrrolo[3,4-c]pyrrole-1,4-dione-alt-thieno[3,2-b]thiophene], PDPP(6-DO)2TT, with the electron-deficient compound hexafluorotetracyanonaphthoquinodimethane (F6TCNNQ). Despite slightly negative HOMOdonor–LUMOacceptor offset −0.12 eV which may suggest reduced driving force for charge transfer (CT), partial CT...
The stability and electronic properties of complexes single-walled carbon nanotubes wrapped by homopolymeric single-stranded DNA molecules (CNT@DNA) are considered using a quantum mechanical density-functional tight-binding method (DFTB). A phenomenological model the CNT@DNA formation energy depending on nanotube radii is developed, which shows that decoration CNT few chains leads to high water solubility CNT@DNA. Pyrimidine-based DNAs found be more effective wrap CNTs than other DNAs....
Opening the window: Hollow multilayer nano-octahedra (see TEM image and structure) often appear in laser-ablation products of layered transition-metal chalcogenides. Calculations on MoS2 nanoparticles demonstrate that exist a window stability between nanoplatelets spherical fullerene-like nanoparticles. Tungsten molybdenum dichalcogenides have structure similar to graphite. (inorganic fullerenes (IFs)) nanotubes (INTs)) been synthesized from these inorganic compounds.1–3 Theoretical...
We have studied the atomic-scale structure of Mo6S6 nanowires using scanning tunneling microscopy and spectroscopy (STM STS) density functional theory (DFT). A novel synthesis route based on metallic Mo precursors is presented for selective formation elementary pure nanowires. The selectively organize as trimer bundles, each consists an electrically conducting backbone dressed with a sulfur exterior cap. may thus be interest building blocks in nanoelectronics because exist robust, singular...
We report on pairs of converging-diverging spin vortices in $\mathrm{Co}/\mathrm{Rh}/\mathrm{NiFe}$ trilayer disks. The lateral magnetization distribution these effective merons is directly imaged by means element-selective x-ray microscopy. By this method, both the divergence and circulation states individual layers are identified to be antisymmetric. Reversal measurements corresponding continuous films reveal that biquadratic interlayer exchange coupling cause for meron pair formation....
CONSPECTUS: Nanostructures based on molybdenum disulfide (MoS2) are by far the most common and well-studied systems among two-dimensional (2D) semiconducting materials. Although still being characterized as a "promising material", catalytic activity of MoS2 nanostructures has been found, applications in lubrication processes pursued. Because exfoliation techniques have improved over past years, monolayer is easily at hand; thus, experimental studies its electronic properties applicability...
A major goal of molecular electronics is the development and implementation devices such as single‐molecular switches. Here, measurements are presented that show controlled in situ switching diarylethene molecules from their nonconductive to conductive state contact gold nanoelectrodes via light irradiation. Both conductance quantum yield for these within a range making suitable actual devices. The junctions opened closed states characterized level E 0 , which dominates current transport...
Star-shaped mesogens with a phloroglucinol or trimesic acid core and oligobenzoate arms up to five repeating units have been synthesised. These non-conventional form various columnar mesophases over broad temperature range. The liquid-crystal phases were characterised by optical microscopy, differential scanning calorimetry, X-ray diffraction, dilatometry solid-state NMR spectroscopy. In addition the high-temperature hexagonal phases, self-assemblies undulate upon cooling consequently...
Local reversible structural changes in ${\mathrm{SrTiO}}_{3}$ single crystals an external electric field are induced by oxygen redistribution. We present situ x-ray diffraction measurements during and immediately after electroformation. Several reflections monitored show elongation of the cubic unit cell strontium titanate. Raman investigations verify that expansion involves a transition from centrosymmetric to lower symmetry phase. During complete formation cycle, including hold time...
The combination of computational methods and advanced characterization techniques is used to highlight the role intramolecular hydrogen bond in thienyldiketopyrrolopyrrole (ThDPPTh) copolymerized with tetrafluorobenzene (F4) PThDPPThF4. We investigate how torsion potentials ThDPPTh isoelectronic dithiazolyldiketopyrrolopyrrole (TzDPPTz) are influenced by bonding translate into different conformation, molecular, structural, opto-electronic characteristics. exhibits N,S-syn orientation most...
Besides graphene, further honeycomb 2D structures were successfully synthesized on various surfaces. However, almost flat plumbene hosting topologically protected edge states could not yet be realized. In this Letter, we investigated the intercalation of Pb buffer layers SiC(0001). Thereby, suspended and charge neutral graphene emerged, intercalated formed lattices, which are rotated by ±7.5° with respect to graphene. Along twist, a proximity-induced modulation hopping parameter in opens...
MoS2 nanooctahedra are believed to be the smallest stable closed-cage structures of MoS2, i.e., genuine inorganic fullerenes. Here a combination experiments and density functional tight binding calculations with molecular dynamics annealing used elucidate electronic properties octahedral Through use these octahedra were found beyond nMo > 100 but loss 12 sulfur atoms in six corners. In contrast bulk nanotubular which semiconductors, Fermi level is situated within band, thus making them...
We investigate the structural, electronic, and transport properties of mechanically deformed Mo6S6 nanowires using a density-functional based tight binding method extended with Green's functions formalism. present two interesting results: first, wire are not affected by bending, second, metal-insulator transition occurs when is twisted. This indicates that molybdenum sulfide can be used as nanocable to flexibly transfer information between electromechanical switches, which also constructed...
The $R$${}_{2}$PdSi${}_{3}$ intermetallic compounds have been reported to crystallize in a hexagonal AlB${}_{2}$-derived structure, with the rare earth atoms on Al sites and Pd Si randomly distributed B sites. However, intricate magnetic properties observed series of always suggested complications assumed structure. To clarify situation, x-ray neutron diffraction measurements were performed heavy $R=\text{Gd}$, Tb, Dy, Ho, Er, Tm, which revealed existence crystallographic superstructure....
Abstract Closed capped WS 2 nanotubes with diameters from 30 to 110 nm are studied by high resolution transmission electron microscopy (HRTEM). The tubes exhibit preferentially a hexagonal stacking order. Atomic images of diameter tube reveal zigzag chirality. A lattice expansion in c‐axis direction ≤11% is found within the outermost triple layers. caps often display regular polygon angles. Structural defects like grain boundaries, non‐planar layers, dislocations, platelet‐like fragments,...
Defect-induced ferromagnetism has triggered a lot of investigations and controversies. The major issue is that the induced ferromagnetic signal so weak it can sufficiently be accounted for by trace contamination. To resolve this issue, we studied variation magnetic properties SiC after neutron irradiation with fluence covering four orders magnitude. A large paramagnetic component been scales up defect concentration, which well uncoupled divacancies. However, contribution still only appears...
We present a detailed investigation of the magnetic properties in SiC single crystals bombarded with neon ions. Through careful measuring magnetization virgin and irradiated SiC, we decompose into paramagnetic, superparamagnetic, ferromagnetic contributions. The contribution persists well above room temperature exhibits pronounced anisotropy. qualitatively explain as result intrinsic clustering tendency defects.