Refine
Year of publication
- 2020 (246) (remove)
Document Type
- Article (177)
- Postprint (35)
- Doctoral Thesis (31)
- Monograph/Edited Volume (1)
- Other (1)
- Review (1)
Is part of the Bibliography
- yes (246)
Keywords
- diffusion (16)
- anomalous diffusion (7)
- model (6)
- perovskite solar cells (6)
- random diffusivity (5)
- dynamics (4)
- impact (4)
- methods: numerical (4)
- photoluminescence (4)
- subdwarfs (4)
- surface (4)
- climate (3)
- coupled rotators (3)
- electrons (3)
- first-passage (3)
- fractional Brownian motion (3)
- hysteresis (3)
- magnetosphere (3)
- mid-temperature transition (3)
- noisy systems (3)
- non-fullerene acceptors (3)
- organic solar cells (3)
- physics education (3)
- stars: abundances (3)
- synchronization transition (3)
- 2D perovskites (2)
- AG (2)
- Aluminum alloys (2)
- Amazon rainforest (2)
- Antibiotics (2)
- Atlantic meridional overturning circulation (2)
- BL Lacertae objects: individual (2)
- Bacterial biofilms (2)
- Biofilms (2)
- Biological defense mechanisms (2)
- Brownian motion (2)
- Cystic fibrosis (2)
- Datenassimilation (2)
- Dielectric Relaxation Spectroscopy (DRS) (2)
- Differential Scanning Calorimetry (DSC) (2)
- Diffusion (2)
- Donor-Acceptor (DA) interface (2)
- Galaktische Archäologie (2)
- Greenland (2)
- ISM: supernova remnants (2)
- ISOS-L-1I protocol (2)
- Kuramoto (2)
- Kuramoto model (2)
- L-Asterisk (2)
- MU-M (2)
- Ornstein–Uhlenbeck process (2)
- Pseudomonas aeruginosa (2)
- Rashba effect (2)
- Rashba-Effekt (2)
- Resolved and unresolved sources as a function of wavelength (2)
- Sputum (2)
- X-ray emission (2)
- X-ray photoelectron spectroscopy (2)
- X-ray probe (2)
- actin polymerization (2)
- activator–inhibitor models (2)
- astroparticle physics (2)
- atomic force microscopy (AFM) (2)
- azobenzene (2)
- bidirectional reflectance (2)
- bifurcation theory (2)
- cesium lead halides (2)
- chains (2)
- channel (2)
- complex networks (2)
- consequences (2)
- continuous time random walk (2)
- costs (2)
- crystal orientation (2)
- diffraction (2)
- diselenide (2)
- donor (2)
- droughts (2)
- efficiency (2)
- electron-transfer (2)
- energy (2)
- ensemble and time averaged mean squared displacement (2)
- entropy production (2)
- excitonic materials (2)
- expanding medium (2)
- exploit (2)
- exposed water ice (2)
- extremal values (2)
- fastest first-passage time of N walkers (2)
- ferroelectric polymers (2)
- flagellum (2)
- fluorinated organic spacer (2)
- galaxies (2)
- galaxies: high-redshift (2)
- gamma rays: general (2)
- gamma-rays: general (2)
- gas phase electron spectroscopy (2)
- global surface warming (2)
- grafted polymers (2)
- heterojunction silicon solar cells (2)
- ice absorption features (2)
- individual (2)
- inorganic perovskites (2)
- instability (2)
- interfaces (2)
- interstellar ice (2)
- ion mobility spectrometry (2)
- line: profiles (2)
- low (2)
- machine learning (2)
- mass conservation (2)
- maximum and range (2)
- metal halide perovskites (2)
- methods: observational (2)
- molecular bottle brushes (2)
- molecular dynamics (2)
- murchison meteorite (2)
- nanoparticles (2)
- non-Gaussianity (2)
- non-radiative interface recombination (2)
- nonfullerene acceptors (2)
- nonlinear waves (2)
- numerical simulations (2)
- ocean heat uptake (2)
- organic photovoltaics (2)
- organic solar cell (2)
- origins (2)
- pattern formation (2)
- phase purity (2)
- phase transition (2)
- photo-isomerization kinetics (2)
- photo-sensitive surfactant (2)
- photocurrent generation (2)
- photon recycling (2)
- photostability (2)
- photovoltaics (2)
- piezoelectric polymers (2)
- planets and satellites: atmospheres (2)
- poly (acrylic acid, sodium salt) (2)
- power spectrum (2)
- pre-service teachers (2)
- prediction (2)
- projections (2)
- pyroelectric polymers (2)
- quantum mechanics (2)
- quasi-Fermi level (2)
- quasi-steady-state photoinduced absorptions (2)
- radiation belts (2)
- recombinations (2)
- repertory grid (2)
- resolution infrared-spectroscopy (2)
- seperation (2)
- sequence-controlled polymers (2)
- shock waves (2)
- single chain folding (2)
- single trajectories (2)
- soft X-ray beamline (2)
- soft X-ray spectroscopy (2)
- solar coronal mass ejections (2)
- solar storm (2)
- space-dependent diffusivity (2)
- spatial localization (2)
- specific surface area (2)
- spectra (2)
- splitting (2)
- star formation (2)
- stars (2)
- stars: activity (2)
- stars: atmospheres (2)
- stars: evolution (2)
- stars: low-mass (2)
- stationary stochastic process (2)
- statistics (2)
- stellar coronal mass ejections (2)
- subdiffusion (2)
- tandem solar cells (2)
- temperature (2)
- temperature dependence (2)
- thermodynamics (2)
- thin films (2)
- time (2)
- transfer dynamics (2)
- vinylidenefluoride (VDF)-based polymers (2)
- voltage losses (2)
- young stellar objects (2)
- 3D field calculations (1)
- 3D printing (1)
- 3D-Feldsimulationen (1)
- ANFO (1)
- APCI (1)
- ARPES (1)
- ASR-sensitive aggregate (1)
- Absorption (1)
- Anisotropy (1)
- Answer Set Programming (1)
- Arctic-midlatitude linkages (1)
- Arktis (1)
- Astronomical instrumentation (1)
- Astrophysics (1)
- Astrophysik (1)
- Astroteilchenphysik (1)
- Atmosphäre (1)
- Atomic Force Microscope (1)
- Azobenzene containing surfactant (1)
- Azobenzol enthaltende Moleküle (1)
- Azobenzol enthaltendes Tensid (1)
- BESSY II (1)
- BESSY II. (1)
- Bayesian inference (1)
- Bending energy (1)
- Bessel functions (1)
- Beugungseffizienz (1)
- Biegeenergie (1)
- Biofilme (1)
- Black– Scholes model (1)
- Bloch-Torrey equation (1)
- Boundary value problem (1)
- Brownian diffusion (1)
- Cattaneo equation (1)
- Ce/Zr (1)
- Cell-cell adhesion (1)
- Churyumov-Gerasimenko (1)
- Colombia (1)
- Conic compartments (1)
- Creep (1)
- CryoSat-2 (1)
- CuI (1)
- Data assimilation (1)
- Dielektrophorese (1)
- Diffusion NMR (1)
- Dislocation motion (1)
- Dispersion force (1)
- Dwarf galaxies (1)
- Dynamical systems (1)
- EBSD (1)
- Einzel-Objekt-Nachweis (1)
- Einzelmolekül-Biosensor (1)
- El Niño-Southern Oscillation (ENSO) (1)
- El Niño-Südliche Oszillation (1)
- Elektret (1)
- Experimental Physics (1)
- Experimentalphysik (1)
- Experimente (1)
- Explainable AI (1)
- F-region dynamo currents (1)
- FELS (1)
- Fe-Ni-Meteorite (1)
- Fibre-fed spectroscopy (1)
- Flims (1)
- Flow (1)
- Fluorescence fluctuation spectroscopy (1)
- Fluoreszenz-Mikroskopie (1)
- Fluoreszenzfluktuationsspektroskopie (1)
- Fluoreszenzproteine (1)
- Fokker– Planck equation (1)
- Forecasting (1)
- Formgleichungen von Vesikeln (1)
- Forschend Entdeckendes Lernen (1)
- Fox H-function (1)
- Fox H-functions (1)
- Fractal (1)
- Fractals (1)
- Fraktale (1)
- GRACE-FO (1)
- Galactic Archaeology (1)
- Galactic archaeology (1)
- Galaxien (1)
- Galaxienbalken (1)
- Galaxienbulges (1)
- Galaxienentwicklung (1)
- Galaxienstruktur (1)
- Galaxy: evolution (1)
- Gammastrahlung (1)
- Gammastrahlungsastronomie (1)
- Genetic programming (1)
- Geochemistry (1)
- Geomagnetic activity (1)
- Geomagnetische Aktivität (1)
- Gitterdynamik (1)
- Gold (1)
- Graphen (1)
- Green function (1)
- Green's function (1)
- Grenzflächenrekombination (1)
- HESS J1825-137 gamma-rays (1)
- Halo der Milchstraße (1)
- Hermite polynomial expansion (1)
- Heterogenität (1)
- Hydrogen activation (1)
- Hydrophobic and hydrophillic interactions (1)
- ICON (1)
- IMAGE EUV (1)
- IR-MALDI (1)
- ISM (1)
- ISM: clouds (1)
- ISM: individual objects: Tycho's SNR (1)
- ISM: jets and outflows (1)
- Inner magnetosphere (1)
- Innere Magnetosphäre (1)
- Integrale Feldspektroskopie (1)
- Inter-hemispheric (1)
- Isomerisierung Kinetik (1)
- Jahreszeitenvorhersage (1)
- Janus colloids (1)
- Janus-Kolloid (1)
- Kalman Filter (1)
- Kalman filter (1)
- Kegelförmige Geometrien (1)
- Kinetics of photoisomerization (1)
- Klima (1)
- Klimatologie (1)
- Kp index (1)
- Kp-Index (1)
- L-edge spectroscopy (1)
- LDDO (1)
- Ladungsspeicherung und -transport (1)
- Lernumgebung (1)
- Levy walk (1)
- Licht-Materie-Wechselwirkung (1)
- Light-Matter Coupling (1)
- Localization regime (1)
- MHD (1)
- Machine learning (1)
- Machine learning control (1)
- Magellanic Cloud (1)
- Magellanic Clouds (1)
- Magellansche Wolken (1)
- Maschinelles Lernen (1)
- Metal-poor stars (1)
- Metallarme Sterne (1)
- Meteorologie (1)
- Migration (1)
- Milchstraße (1)
- Milky Way (1)
- Milky Way Halo (1)
- Min-Proteine (1)
- Min-proteins (1)
- Modal expansion method (1)
- Modeling (1)
- Modellieren (1)
- Molecular motors (1)
- Molekulare Motoren (1)
- Moonlets (1)
- Motivation (1)
- Multi-object spectroscopy (1)
- Multimode fibres (1)
- Nano-Elektroden (1)
- Nanoparticles (1)
- Nanopartikel (1)
- Neural networks (1)
- Neuronale Netze (1)
- Non-perturbative analysis (1)
- Oberflächengitter (1)
- Ornstein-Uhlenbeck Process (1)
- Ornstein-Uhlenbeck Prozess (1)
- P(VDF-TFE) copolymer (1)
- PEDOT:PSS (1)
- Perceived Relevance (1)
- Percolation (1)
- Perkolation (1)
- Perovskite solar cells (1)
- Perowskit (1)
- Perowskit Solarzellen (1)
- Photochemie (1)
- Photochemistry (1)
- Photopolymer (1)
- Photostrukturierung von Polymerfilmen (1)
- Photovoltaik (1)
- Physics Education (1)
- Physics Problems (1)
- Physikaufgaben (1)
- Physikdidaktik (1)
- Plasma Physics (1)
- Plasmasphere (1)
- Plasmasphäre (1)
- Plasmonen (1)
- Plasmons (1)
- Platform magnetometers (1)
- Polypropylen (1)
- Polystyrol Nano-Sphären (1)
- Porous silica particles (1)
- Prognose (1)
- Propellers (1)
- R-PE (1)
- REM (1)
- Random Environments (1)
- Random Walk (1)
- Rare elements (1)
- Rasterkraftmikroskopie (1)
- Reactive adsorption (1)
- Repertory Grid (1)
- Resonances (1)
- Rings (1)
- Ringstromelektronen (1)
- SEM (1)
- Saturn (1)
- Schottky junction (1)
- Schrödinger equation (1)
- Seasonal prediction (1)
- Shape equations of vesicles (1)
- Shockley-Read-Hall (1)
- Small (1)
- Smartphone (1)
- Solarzellen (1)
- Space mining (1)
- Spin Textur (1)
- Spin-echo (1)
- Sterne (1)
- Sternenpopulationen (1)
- Strahlungsgürtel (1)
- Stratosphere-troposphere coupling (1)
- Stratospheric polar vortex (1)
- Stratosphären-Troposphären-Kopplung (1)
- Stratosphärischer Polarwirbel (1)
- Streuresonanzen (1)
- Supernovaüberrest (1)
- Surface Relief Grating (SRG) (1)
- Surface properties (1)
- Svalbard (1)
- Synchronization control (1)
- Teilchenbeschleunigung (1)
- Ti-6Al-4V (1)
- Topological Crystalline Insulator (1)
- Topological Insulator (1)
- Topologischer Isolator (1)
- Topologischer kristalliner Isolator (1)
- Validation (1)
- Validierung (1)
- Verbindungspfade zwischen der Arktis und den mittleren Breiten (1)
- WAAM (1)
- Wellen-Teilchen Wechselwirkungen (1)
- Wismut (1)
- X-ray (1)
- X-ray absorption (1)
- X-ray computed tomography (CT) (1)
- X-ray refraction (1)
- X-ray stars (1)
- X-rays: individual: GJ 1151 (1)
- X-rays: stars (1)
- XCT (1)
- Zell-zell Adhäsion (1)
- Zufällige Stochastische Irrfahrt (1)
- Zufällige Umgebungen (1)
- Zwerg Galaxien (1)
- absorption (1)
- acceleration of particles (1)
- active solar (1)
- active solar chromosphere (1)
- activity - sun (1)
- actuators (1)
- adaptation and mitigation (1)
- additive manufacturing (1)
- aggregation (1)
- alkali-silica reaction (ASR) (1)
- amphiphilic side chains (1)
- analysis - techniques (1)
- and governance (1)
- anomalous (or non-Fickian) diffusion (1)
- anomalous heat conduction (1)
- arctic (1)
- astrophysical plasmas (1)
- astrophysics (1)
- asynchronous design (1)
- atmosphere (1)
- atmosphere - sun (1)
- automated image processing (1)
- axial next nearest neighbour Ising chains (1)
- azobenzene containing molecules (1)
- background (1)
- barrier escape (1)
- basis-sets (1)
- binaries: eclipsing (1)
- binaries: general (1)
- binaries: spectroscopic (1)
- biofilms (1)
- biophysics (1)
- bismuth (1)
- blade (1)
- blended learning (1)
- built-in potential (1)
- bulk-heterojunction solar cells (1)
- bumps (1)
- capacitance spectroscopy (1)
- carrier density (1)
- catalogs (1)
- celestial mechanics (1)
- charge (1)
- charge carrier density (1)
- charge carrier extraction (1)
- charge collection (1)
- charge injection across hybrid interfaces (1)
- charge storage and transport (1)
- charge transport layers (1)
- charge-transfer (1)
- charge-transfer excitations (1)
- chemische Oberflächen-Modifikationen (1)
- chimera states (1)
- chromosphere - methods (1)
- circumstellar matter (1)
- climatology (1)
- coma (1)
- comets (1)
- comets: general (1)
- comets: individual: 67P (1)
- components (1)
- computed tomography (1)
- concrete (1)
- conductivity (1)
- conformational and hydrodynamic characteristics (1)
- conjugated polymers (1)
- connections between chaos and statistical physics (1)
- convolutional neural networks (1)
- copper iodide (1)
- corona (1)
- cosmic rays (1)
- crack (1)
- creep (1)
- critical adsorption (1)
- crossover dynamics (1)
- crystal (1)
- crystalline phases (1)
- damage quantification (1)
- data (1)
- data assimilation (1)
- data processing (1)
- deep learning (1)
- delay faults (1)
- density (1)
- dependent velocity (1)
- deposition (1)
- design for Testability (1)
- detection (1)
- dielectric (1)
- dielectric properties (1)
- dielectrophoresis (1)
- diffraction efficiency (1)
- diffusing diffusivity (1)
- diffusion-radation mechanisms (1)
- diffusioosmotic flow (1)
- diffusioosmotischer Fluss (1)
- dislocations (1)
- distortion (1)
- driven (1)
- driving force (1)
- dub-ambient (1)
- dust (1)
- dynamic loading (1)
- dynamical systems (1)
- dynamo (1)
- ecology and biodiversity (1)
- electret (1)
- electret polymers (1)
- electro-electrets (1)
- electron flux (1)
- electron localization (1)
- electronic structure (1)
- electrostatics (1)
- elevated-temperature effects on the operation of dielectric-elastomer (1)
- empirical modeling (1)
- enacted PCK (1)
- energetic disorders (1)
- energy-level alignments (1)
- experiment (1)
- explosives (1)
- extrusion (1)
- ferroelectricity and piezoelectricity in polymers (1)
- field experience (1)
- field-aligned currents (1)
- film (1)
- films (1)
- first passage (1)
- fluorescence microscopy (1)
- fluorescent proteins (1)
- fluorination (1)
- formal specification (1)
- formal verification (1)
- formation (1)
- fractal (1)
- fractal dimension (1)
- fractional dynamic equations (1)
- fullerenes (1)
- functional materials (1)
- fungus (1)
- galaxies: formation (1)
- galaxy bars (1)
- galaxy bulges (1)
- galaxy evolution (1)
- galaxy structure (1)
- gamma rays (1)
- gamma rays: (1)
- gamma rays: diffuse (1)
- gamma-ray astronomy (1)
- gas (1)
- gas chromatography (1)
- general (1)
- genomic DNA conformation (1)
- geometric Brownian motion (1)
- granite (1)
- graphene (1)
- hatural language (1)
- heat-treatment (1)
- high field mobility (1)
- high resolution spectroscopy (1)
- high strain rate (1)
- hole (1)
- human behaviour (1)
- humidity (1)
- hybrid manufacturing (1)
- hybrid material (1)
- hybrid metal oxides (1)
- hybrid synthesis (1)
- hydrodynamics (1)
- hydrophoben und hydrophile Wechselwirkungen (1)
- impedance spectroscopy (1)
- inquiry based learning (1)
- instabilities (1)
- instructional (1)
- instructional explanation (1)
- integral field spectroscopy (1)
- interfacial recombination (1)
- inversion (1)
- iron (1)
- iron cyanides (1)
- kinetic-theory (1)
- large deviation theory (1)
- lattice dynamics (1)
- learning environment (1)
- light photocontrol (1)
- low donor content (1)
- magnetic beads (1)
- magnetic fields (1)
- magnetism (1)
- manipulation (1)
- mass (1)
- massive stars (1)
- mathematical modeling (1)
- mathematische Modellierung (1)
- matrix composites (1)
- mechanical and acoustical properties (1)
- mechanical properties (1)
- mechanische und akustische Eigenschaften (1)
- mechanobiology (1)
- melting slm (1)
- metal (1)
- meteorology (1)
- methane localization (1)
- mhd turbulence (1)
- microstructure-property relations (1)
- miscellaneous (1)
- mobility (1)
- modelling (1)
- models (1)
- modular logic programs (1)
- mold (1)
- molecular brushes (1)
- molecular crystals (1)
- molecular hydrodynamics and (1)
- molecular overcrowding (1)
- molecular weight (1)
- molecules (1)
- motion (1)
- motivation (1)
- nano-electrodes (1)
- nanoscale heat transfer (1)
- nanoskaliger Wärmetransport (1)
- natural resources (biological and non-biological) (1)
- nebulae: general (1)
- networks (1)
- neutron (1)
- nichtstrahlende Verluste (1)
- non-Langevin reduction factors (1)
- non-gaussianity (1)
- non-integer dimension (1)
- non-thermal-pulsars (1)
- nonergodicity (1)
- nonlinear dynamics (1)
- nonradiative losses (1)
- optics (1)
- option pricing (1)
- organic interfaces (1)
- p-type (1)
- parallel immobilization of biomolecules (1)
- parallele Immobilisierung von Biomolekülen (1)
- parameter (1)
- particle acceleration (1)
- peptides (1)
- perovskite (1)
- phase transitions (1)
- phase-transition boundary (1)
- photo-chemical pathways (1)
- photo-structuring of polymer films (1)
- photochemistry (1)
- photoexcited hole transfer (1)
- photoisomerization (1)
- photosensitive Polymer (1)
- piezoelectrets (1)
- planet (1)
- planet-star interactions (1)
- planetary (1)
- planetary nebulae: individual: SwSt1 (1)
- planets (1)
- planets and satellites: gaseous (1)
- planets and satellites: rings (1)
- plasma flows (1)
- policies (1)
- politics (1)
- poly(vinylidenefluoride-trifluoroethylene) P(VDF-TrFE) (1)
- polyelectrolytes (1)
- polymer ferroelectrets (1)
- polymer solar cells (1)
- polypropylene (1)
- polystyrene nano-spheres (1)
- populations (1)
- pore orientation (1)
- porosity (1)
- poröse Siliciumdioxidpartikel (1)
- power conversion efficiency (1)
- power spectral analysis (1)
- practicum (1)
- pre-main sequence stars (1)
- preferred orientation (1)
- pressure (1)
- printed electroacoustic thin-film transducers (1)
- printing (1)
- processing (1)
- professional knowledge (1)
- protostars (1)
- pulsars: individual: LS V+22 25 (1)
- quality (1)
- quantum (1)
- quantum correlations (1)
- quasi-particles (1)
- radiation mechanisms: non-thermal (1)
- recombination order (1)
- reflection (1)
- resetting (1)
- residual stress (1)
- resonant inelastic X-ray scattering (1)
- resonant inelastic X-ray scattering; (1)
- ring current electrons (1)
- scattering (1)
- scattering resonances (1)
- school internship (1)
- screen (1)
- segmentations (1)
- sensors and actuators (1)
- silver (1)
- simulations (1)
- single-molecule biosensor (1)
- single-object detection (1)
- soft X-ray (1)
- soft X-ray absorption (1)
- soft electro-active materials (1)
- soft matter (1)
- solar cells (1)
- solar chromosphere (1)
- solar filament eruptions (1)
- solubility test (1)
- solvation (1)
- spectrometry (1)
- spectroscopic - astronomical databases (1)
- spectroscopy (1)
- spektrale Leistungsdichte (1)
- spin texture (1)
- spin-crossover (1)
- split Hopkinson pressure bar (1)
- star interactions (1)
- stars: AGB and post-AGB (1)
- stars: chemically peculiar (1)
- stars: coronae (1)
- stars: early-type (1)
- stars: fundamental parameters (1)
- stars: horizontal branch (1)
- stars: horizontal-branch (1)
- stars: individual: V1298 Tau (1)
- stars: late-type (1)
- stars: mass-loss (1)
- stars: massive (1)
- stars: rotation (1)
- stars: solar-type (1)
- stars: variables: general (1)
- statistical physics (1)
- stellar content (1)
- stellar populations (1)
- stochastic dynamics (1)
- stochastic processes (1)
- stress exponent (1)
- stretching (1)
- structure (1)
- structures (1)
- stuck-at faults (1)
- sub-diffraction gratings (1)
- sun (1)
- superalloys (1)
- superdiffusion and (1)
- supernova remnant (1)
- surface chemical treatment (1)
- surface recombination (1)
- synchronization (1)
- synthesis (1)
- teacher professional development (1)
- techniques: photometric (1)
- techniques: spectroscopic (1)
- telegrapher's equation (1)
- telluride (1)
- tellurium (1)
- texture (1)
- the sun (1)
- thermal stimulation of (1)
- thermally enhanced actuators (1)
- thermoelectrics (1)
- thick junctions (1)
- timing resilient design (1)
- tissue growth (1)
- tranfer excited-state (1)
- transcrystalline polypropylene (1)
- transition metal complexes (1)
- transkristallines Polypropylen (1)
- transparent conductors (1)
- transport properties (1)
- ultrafast magnetism (1)
- ultrafast x-ray diffraction (1)
- ultraschnelle Röntgendiffraktion (1)
- ultraschneller Magnetimus (1)
- vibrational spectroscopy (1)
- water-interface (1)
- water-methane films (1)
- wave-particle interactions (1)
- weak ergodicity breaking (1)
- work function (1)
- x-ray-absorption (1)
- young star clusters (1)
- zufälligen Diffusivität (1)
- wahrgenommene Relevanz (1)
Institute
- Institut für Physik und Astronomie (246) (remove)
The combined effect of ultraviolet (UV) light soaking and self-assembled monolayer deposition on the work function (WF) of thin ZnO layers and on the efficiency of hole injection into the prototypical conjugated polymer poly(3-hexylthiophen-2,5-diyl) (P3HT) is systematically investigated. It is shown that the WF and injection efficiency depend strongly on the history of UV light exposure. Proper treatment of the ZnO layer enables ohmic hole injection into P3HT, demonstrating ZnO as a potential anode material for organic optoelectronic devices. The results also suggest that valid conclusions on the energy-level alignment at the ZnO/organic interfaces may only be drawn if the illumination history is precisely known and controlled. This is inherently problematic when comparing electronic data from ultraviolet photoelectron spectroscopy (UPS) measurements carried out under different or ill-defined illumination conditions.
We show that, although the equilibrium band dispersion of the Shockley-type surface state of two-dimensional Au(111) quantum films grown on W(110) does not deviate from the expected free-electron-like behavior, its nonequilibrium energy-momentum dispersion probed by time- and angle-resolved photoemission exhibits a remarkable kink above the Fermi level due to a significant enhancement of the effective mass. The kink is pronounced for certain thicknesses of the Au quantum well and vanishes in the very thin limit. We identify the kink as induced by the coupling between the Au(111) surface state and emergent quantum-well states which probe directly the buried gold-tungsten interface. The signatures of the coupling are further revealed by our time-resolved measurements which show that surface state and quantum-well states thermalize together behaving as dynamically locked electron populations. In particular, relaxation of hot carriers following laser excitation is similar for both surface state and quantum-well states and much slower than expected for a bulk metallic system. The influence of quantum confinement on the interplay between elementary scattering processes of the electrons at the surface and ultrafast carrier transport in the direction perpendicular to the surface is shown to be the reason for the slow electron dynamics.
We show that, although the equilibrium band dispersion of the Shockley-type surface state of two-dimensional Au(111) quantum films grown on W(110) does not deviate from the expected free-electron-like behavior, its nonequilibrium energy-momentum dispersion probed by time- and angle-resolved photoemission exhibits a remarkable kink above the Fermi level due to a significant enhancement of the effective mass. The kink is pronounced for certain thicknesses of the Au quantum well and vanishes in the very thin limit. We identify the kink as induced by the coupling between the Au(111) surface state and emergent quantum-well states which probe directly the buried gold-tungsten interface. The signatures of the coupling are further revealed by our time-resolved measurements which show that surface state and quantum-well states thermalize together behaving as dynamically locked electron populations. In particular, relaxation of hot carriers following laser excitation is similar for both surface state and quantum-well states and much slower than expected for a bulk metallic system. The influence of quantum confinement on the interplay between elementary scattering processes of the electrons at the surface and ultrafast carrier transport in the direction perpendicular to the surface is shown to be the reason for the slow electron dynamics.
The performance of the recently commissioned spectrometer PEAXIS for resonant inelastic soft X-ray scattering (RIXS) and X-ray photoelectron spectroscopy and its hosting beamline U41-PEAXIS at the BESSY II synchrotron are characterized. The beamline provides linearly polarized light from 180 eV to 1600 eV allowing for RIXS measurements in the range 200-1200 eV. The monochromator optics can be operated in different configurations to provide either high flux with up to 10(12) photons s(-1) within the focal spot at the sample or high energy resolution with a full width at half maximum of <40 meV at an incident photon energy of similar to 400 eV. The measured total energy resolution of the RIXS spectrometer is in very good agreement with theoretically predicted values obtained by ray-tracing simulations. PEAXIS features a 5 m-long RIXS spectrometer arm that can be continuously rotated about the sample position by 106 degrees within the horizontal photon scattering plane, thus enabling the study of momentum-transfer-dependent excitations. Selected scientific examples are presented to demonstrate the instrument capabilities, including measurements of excitations in single-crystalline NiO and in liquid acetone employing a fluid cell sample manipulator. Planned upgrades of the beamline and the RIXS spectrometer to further increase the energy resolution to similar to 100 meV at 1000 eV incident photon energy are discussed.
The power conversion efficiency (PCE) of state-of-the-art organic solar cells is still limited by significant open-circuit voltage (V-OC) losses, partly due to the excitonic nature of organic materials and partly due to ill-designed architectures. Thus, quantifying different contributions of the V-OC losses is of importance to enable further improvements in the performance of organic solar cells. Herein, the spectroscopic and semiconductor device physics approaches are combined to identify and quantify losses from surface recombination and bulk recombination. Several state-of-the-art systems that demonstrate different V-OC losses in their performance are presented. By evaluating the quasi-Fermi level splitting (QFLS) and the V-OC as a function of the excitation fluence in nonfullerene-based PM6:Y6, PM6:Y11, and fullerene-based PPDT2FBT:PCBM devices with different architectures, the voltage losses due to different recombination processes occurring in the active layers, the transport layers, and at the interfaces are assessed. It is found that surface recombination at interfaces in the studied solar cells is negligible, and thus, suppressing the non-radiative recombination in the active layers is the key factor to enhance the PCE of these devices. This study provides a universal tool to explain and further improve the performance of recently demonstrated high-open-circuit-voltage organic solar cells.
Ammonium salts are a reservoir of nitrogen on a cometary nucleus and possibly on some asteroids
(2020)
The measured nitrogen-to-carbon ratio in comets is lower than for the Sun, a discrepancy which could be alleviated if there is an unknown reservoir of nitrogen in comets. The nucleus of comet 67P/Churyumov-Gerasimenko exhibits an unidentified broad spectral reflectance feature around 3.2 micrometers, which is ubiquitous across its surface. On the basis of laboratory experiments, we attribute this absorption band to ammonium salts mixed with dust on the surface. The depth of the band indicates that semivolatile ammonium salts are a substantial reservoir of nitrogen in the comet, potentially dominating over refractory organic matter and more volatile species. Similar absorption features appear in the spectra of some asteroids, implying a compositional link between asteroids, comets, and the parent interstellar cloud.
Ammonium salts are a reservoir of nitrogen on a cometary nucleus and possibly on some asteroids
(2020)
The measured nitrogen-to-carbon ratio in comets is lower than for the Sun, a discrepancy which could be alleviated if there is an unknown reservoir of nitrogen in comets. The nucleus of comet 67P/Churyumov-Gerasimenko exhibits an unidentified broad spectral reflectance feature around 3.2 micrometers, which is ubiquitous across its surface. On the basis of laboratory experiments, we attribute this absorption band to ammonium salts mixed with dust on the surface. The depth of the band indicates that semivolatile ammonium salts are a substantial reservoir of nitrogen in the comet, potentially dominating over refractory organic matter and more volatile species. Similar absorption features appear in the spectra of some asteroids, implying a compositional link between asteroids, comets, and the parent interstellar cloud.
Pre-service physics teachers often do not recognise the relevance for their future career in their university content knowledge courses. A lower perceived relevance can, however, have a negative effect on their motivation and on their academic success. Several intervention studies have been undertaken with the goal to increase this perceived relevance. A previous study shows that conceptual physics problems used in university physics courses are perceived by pre-service physics teachers as more relevant for their future career than regular, quantitative problems. It is however not clear, what the students' meaning of the construct 'relevance' is: what makes a problem more relevant to them than another problem? To answer this question, N = 7 pre-service teachers were interviewed using the repertory grid technique, based on the personal construct theory. Nine physics problems were discussed with regards to their perceived relevance and with regards to problem properties that distinguish these problems from each other. We are able to identify six problem properties that have a positive influence on the perceived relevance. Physics problems that are based on these properties should therefore potentially have a higher perceived relevance, which can have a positive effect on the motivation of the pre-service teachers who solve these problems.
A synthesis route to controlled and dynamic single polymer chain folding is reported. Sequence-controlled macromolecules containing precisely located selenol moieties within a polymer chain are synthesized. Oxidation of selenol functionalities lead to diselenide bridges and induces controlled intramolecular crosslinking to generate single chain collapse. The cyclization process is successfully characterized by SEC as well as by H-1 NMR and 2D HSQC NMR spectroscopies. In order to gain insight on the molecular level to reveal the degree of structural control, the folded polymers are transformed into folded molecular brushes that are known to be visualizable as single molecule structures by AFM. The "grafting onto" approach is performed by using triazolinedione-diene reaction to graft the side chain polymers. A series of folded molecular brushes as well as the corresponding linear controls are synthesized. AFM visualization is proving the cyclization of the folded backbone by showing globular objects, where non-folded brushes show typical worm-like structures. (C) 2019 The Authors. Journal of Polymer Science published by Wiley Periodicals, Inc.
A synthesis route to controlled and dynamic single polymer chain folding is reported. Sequence-controlled macromolecules containing precisely located selenol moieties within a polymer chain are synthesized. Oxidation of selenol functionalities lead to diselenide bridges and induces controlled intramolecular crosslinking to generate single chain collapse. The cyclization process is successfully characterized by SEC as well as by H-1 NMR and 2D HSQC NMR spectroscopies. In order to gain insight on the molecular level to reveal the degree of structural control, the folded polymers are transformed into folded molecular brushes that are known to be visualizable as single molecule structures by AFM. The "grafting onto" approach is performed by using triazolinedione-diene reaction to graft the side chain polymers. A series of folded molecular brushes as well as the corresponding linear controls are synthesized. AFM visualization is proving the cyclization of the folded backbone by showing globular objects, where non-folded brushes show typical worm-like structures. (C) 2019 The Authors. Journal of Polymer Science published by Wiley Periodicals, Inc.