Institut für Physik und Astronomie
Refine
Year of publication
- 2017 (281) (remove)
Document Type
- Article (215)
- Doctoral Thesis (26)
- Other (17)
- Postprint (15)
- Review (6)
- Habilitation Thesis (2)
Is part of the Bibliography
- yes (281)
Keywords
- stars: massive (11)
- stars: early-type (8)
- stars: winds, outflows (7)
- Magellanic Clouds (6)
- stars: mass-loss (6)
- X-rays: stars (5)
- acceleration of particles (5)
- cosmic rays (5)
- stars: magnetic field (5)
- X-rays: binaries (4)
- first passage time (4)
- galaxies: active (4)
- galaxies: dwarf (4)
- galaxies: jets (4)
- gamma rays: galaxies (4)
- photochemistry (4)
- radiation mechanisms: non-thermal (4)
- turbulence (4)
- BL Lacertae objects: general (3)
- ISM: supernova remnants (3)
- X-ray refraction (3)
- aspect ratio (3)
- binaries: spectroscopic (3)
- climate change (3)
- cylindrical geometry (3)
- diffusion (3)
- financial time series (3)
- galaxies: evolution (3)
- geometric Brownian motion (3)
- methods: numerical (3)
- organic solar cells (3)
- protein search (3)
- shock waves (3)
- solar wind (3)
- stars: Wolf-Rayet (3)
- stars: atmospheres (3)
- stars: formation (3)
- techniques: imaging spectroscopy (3)
- time averaging (3)
- Auger electron spectroscopy (2)
- Complementarity (2)
- Dark Matter (2)
- Galaxy: evolution (2)
- Galaxy: halo (2)
- Mode function (2)
- Quantum optics (2)
- RIXS (resonant inelastic X-ray scattering) (2)
- Radiation belts (2)
- Sun: activity (2)
- Sun: photosphere (2)
- VERITAS (2)
- Vacuum fields (2)
- astroparticle physics (2)
- galaxies: ISM (2)
- galaxies: interactions (2)
- galaxies: nuclei (2)
- galaxies: starburst (2)
- gamma rays: general (2)
- gamma-rays: galaxies (2)
- infrared: stars (2)
- instabilities (2)
- magnetic fields (2)
- nitrogen (2)
- nonradiative recombination (2)
- open-circuit voltage (2)
- perovskite solar cells (2)
- photofragmentation (2)
- protonation (2)
- radiation belts (2)
- selective bond cleavage (2)
- spectroscopy (2)
- stars: activity (2)
- stars: kinematics and dynamics (2)
- stars: neutron (2)
- stars: winds (2)
- sunspots (2)
- techniques: polarimetric (2)
- ultrafast dynamics (2)
- ultraviolet: ISM (2)
- 3D Modellierung (1)
- 3D-modeling (1)
- ARFIMA (1)
- Accelerometer (1)
- Accretion processes (1)
- Active Galactic Nuclei (1)
- Additive manufacturing (1)
- Aggregate states (1)
- All-polymer heterojunctions (1)
- Alternating copolymers (1)
- Ambipolar charge transport (1)
- Ambipolar materials (1)
- Anomalous diffusion (1)
- Anregungs-Abfrage-Experiment (1)
- Antiferromagnetismus (1)
- Aqueous solution (1)
- Arctic boundary layer (1)
- Asteroseismologie (1)
- Atlantic Meridional Overturning Circulation (1)
- Atmosphärendynamik (1)
- Azobenzol-haltiges Tensid (1)
- BL Lacertae objects: individual (B2 1215+30, VER J1217+301) (1)
- BL Lacertae objects: individual: 1ES 2344+514=VERJ2347+517 (1)
- BL Lacertae objects: individual: Markarian 501 (1)
- BL Lacertae objects: individual: PKS 1424+240 (1)
- BL Lacertae objects: individual: PKS 2155-304 (1)
- Backbone modifications (1)
- Bayesian Model Averaging (1)
- Bayesian estimation (1)
- Beta-eucryptite (1)
- Bilayer solar cells (1)
- Bose-Einstein condensation (1)
- Brechungsindex von Azobenzol-haltigen Tensiden (1)
- CM(-1) (1)
- Chaos synchronization (1)
- Charge extraction (1)
- Charge generation (1)
- Charge recombination (1)
- Charge separation (1)
- Charge-transfer state (1)
- Chemodynamik der Milchstraße (1)
- Cherenkov showers (1)
- Cherenkov-Schauern (1)
- Climate modeling (1)
- Comb model (1)
- Comb-lattice model (1)
- Complete Bernstein function (1)
- Completely monotone function (1)
- Composites (1)
- Compton and Pair Creation Telescope (1)
- Conformational disorder (1)
- Cosmic Antimatter (1)
- Cosmic Rays (1)
- Counterparts of gravitational waves (1)
- Covalent interaction (1)
- Crack detection (1)
- Crystalline phases (1)
- Cylindrical comb (1)
- DFT (1)
- DIC (1)
- DNA damage (1)
- DNA-Schädigung (1)
- Dictyostelium (1)
- Distributed order diffusion-wave equations (1)
- Donor-acceptor copolymers (1)
- Doppelsterne (1)
- Dunkler Materie (1)
- Dynamic loading (1)
- Dynamical systems (1)
- ECIS (1)
- EMIC (1)
- Early Universe (1)
- Electron back-scattered diffraction (1)
- Electron traps (1)
- Energetic disorder (1)
- Energy-level alignment (1)
- Entstehung der Milchstraße (1)
- Entstehung von Galaxien (1)
- Entwicklung von Galaxien (1)
- Escherichia-coli (1)
- Fermi (1)
- Fermi-level alignment (1)
- Fermi-level pinning (1)
- Ferroelektrete (1)
- Ferromagnetismus (1)
- Fokker-Planck equation (1)
- Forcemyography (1)
- Fractal dimension (1)
- Galaxien (1)
- Galaxien: Evolution (1)
- Galaxien: Kinematik und Dynamik (1)
- Galaxien: Statistiken (1)
- Galaxy: abundances (1)
- Galaxy: formation (1)
- Galaxy: structure (1)
- Gamma-Ray Bursts (1)
- Gamma-ray bursts (1)
- Gelatin-NaCMC (1)
- Gelatin-NaPAA composites (1)
- Genetic programming (1)
- Gompertz growth function (1)
- Granite (1)
- H II regions (1)
- Heat Transfer (1)
- Heavy-tails (1)
- High specific surface area (1)
- High-Energy Astrophysics (1)
- High-Energy Gamma-Ray Astronomy (1)
- High-impact polystyrene (1)
- Hitzewellen (1)
- Hybrid materials (1)
- Hydraulic models (1)
- Hydraulic networks (1)
- Hypernetwork (1)
- IACT (1)
- IR ellipsometry (1)
- ISM: individual objects (RX J1713.7-3946, G347.3-0.5) (1)
- ISM: individual objects: IRAS 20286+4105 (1)
- ISM: jets and outflows (1)
- ISM: kinematics and dynamics (1)
- ISM: lines and bands (1)
- ISM: structure (1)
- Instrumentation (1)
- Interface dipole (1)
- Interfacial tension (1)
- Interlayer (1)
- Intermittency (1)
- Intrachain order (1)
- Intragap states (1)
- Janus gels (1)
- Jets (1)
- Jetstream (1)
- Junction model (1)
- Kinematik (1)
- Klimawandel (1)
- Konformationsselektion (1)
- Ladungsträgerrekombination (1)
- Lagrangian statistics (1)
- Leerlaufspannung (1)
- Ligand-field state (1)
- Line Suche (1)
- Local Group (1)
- Long-range dependence (1)
- Lysozyme (1)
- Magnetosomen-Ketten (1)
- Magnetospheric physics (1)
- Markov additive processes (1)
- Markov state models (1)
- Markowketten (1)
- Massive stars (1)
- Maximum entropy method (1)
- Microcracked ceramics (1)
- Microscopic morphology (1)
- Microstructure and texture (1)
- Milky Way chemodynamics (1)
- Milky Way evolution (1)
- Mobility imbalance (1)
- Mobility relaxation (1)
- Model structural error (1)
- Monte Carlo simulation (1)
- Moonlight (1)
- Multiple trapping model (1)
- Multiwavelength Observations of the Universe (1)
- NM (1)
- Nanoparticles (1)
- Nanopartikel (1)
- Near-Field Optics (1)
- Network reconstruction (1)
- Neurooscillators (1)
- Neutron diffraction (1)
- Ni(111) (1)
- Nickel-based superalloy (1)
- Nonlinear analysis (1)
- Nonradiative recombination (1)
- Nuclear Astrophysics (1)
- Nucleosynthesis (1)
- OFET (1)
- Observations (1)
- Observing methods (1)
- Open-circuit voltage (1)
- Optoelectronic properties (1)
- Organic solar cells (1)
- Ott-Antonsen reduction (1)
- Outflows (1)
- PBT7 (1)
- PBTTT (1)
- PCPDTBT (1)
- Partial synchrony (1)
- Partially alternating copolymers (1)
- Particles precipitating (1)
- Particles trapped (1)
- Photo-CELIV (1)
- Photochemie (1)
- Photocurrent (1)
- Photovoltaic gap (1)
- Pickering Janus emulsions (1)
- Piezo-, Pyro-und Ferroelektrizität (1)
- Pipe networks (1)
- Polyetlioxysiloxane (1)
- Polymer intermixing (1)
- Porosity (1)
- Probabilistic projections (1)
- Probability (1)
- Protein-Protein-Interaktion (1)
- Proteinkinetik (1)
- Protonierung (1)
- RIXS (resonante inelastische Röntgenstreuung) (1)
- Radiosensitization (1)
- Recombination losses (1)
- Residual stress (1)
- Resonant inelastic X-ray scattering (1)
- Ring tensiometry (1)
- Rock (1)
- SFXTs (1)
- SHPB (1)
- STM (1)
- Selektiver Bindungsbruch (1)
- SgXBs (1)
- Silicification (1)
- Space mission (1)
- Specific surface (1)
- Spectral diffusion (1)
- Spektroskopie (1)
- Statistical copolymers (1)
- Stellar outflows (1)
- Sternentwicklung (1)
- Sternwinde (1)
- Stickstoff (1)
- Stille-type cross-coupling (1)
- Stimuli-responsive materials (1)
- Strain hardening (1)
- Structure-property relationships (1)
- Sun: chromosphere (1)
- Sun: corona (1)
- Sun: flares (1)
- Sun: heliosphere (1)
- Sun: magnetic fields (1)
- Supernovae (1)
- Surfactant (1)
- Synchronization control (1)
- Talbot-Lau interferometer (1)
- Telekonnektionen (1)
- Tensile load (1)
- Thermal Radiation (1)
- Ti-6Al-4V (1)
- Time delay (1)
- Time series (1)
- Time-dependent mobility (1)
- Time-of-flight (TOF) (1)
- Transient photocurrent (1)
- Transition-metal ion (1)
- UV nanoimprint lithography (1)
- Ultra-high energy cosmic rays (1)
- Ultraviolet photoelectron spectroscopy (1)
- University physics (1)
- VERB code (1)
- Vacuum-level alignment (1)
- Van Allen Probes (1)
- Vibrio Harveyi clade (1)
- Water distribution systems (1)
- Wind-fed systems (1)
- Wolf-Rayet (1)
- X-ray binary (1)
- X-ray imaging (1)
- X-ray phase contrast (1)
- X-ray photoelectron spectroscopy (1)
- X-rays: ISM (1)
- X-rays: individuals: IGRJ16328-4726 (1)
- X-rays: individuals: IGRJ17354-3255 (1)
- X-rays: individuals: IGRJ17544-2619 (1)
- X-rays: individuals: IGRJ18450-0435 (1)
- X-rays: individuals: SAXJ1818.6-1703 (1)
- X-rays: individuals: Vela X-1 (1)
- Zell Bewegung (1)
- Zell-substrat Adhäsion (1)
- actin waves (1)
- adaptation (1)
- additive manufacturing (1)
- algorithms (1)
- antiferromagnetism (1)
- antireflection (1)
- arktische Grenzschicht (1)
- asteroseismology (1)
- asymptotic analysis (1)
- atmosphere dynamics (1)
- atomic displacement parameters (1)
- atomic distances (1)
- azobenzene containing polymer films (1)
- azobenzene refractive index (1)
- azobenzene surfactant (1)
- behavior (1)
- binaries: close (1)
- binary stars (1)
- biochemical oscillators (1)
- bioluminescence (1)
- biophysical model (1)
- biophysics (1)
- bioreceptors (1)
- brain rhythms (1)
- brain synchronization (1)
- carbon nitride (1)
- catalytic azobenzene isomerization (1)
- causal discovery algorithm (1)
- cell movement (1)
- cell nucleus (1)
- cell-substrate adhesion (1)
- cellular signalling (1)
- charge carrier recombination (1)
- charge density (1)
- chemistry (1)
- chemomechanical coupling (1)
- chimera state (1)
- cluster-analysis (1)
- co-monomer content (1)
- coarse-grained order parameter (1)
- collapse (1)
- conformational selection (1)
- conservation laws (1)
- continuous symmetries (1)
- cosmic background radiation (1)
- cosmological simulations (1)
- coupled initial boundary value problem (1)
- critical fluctuations (1)
- crystal texture (1)
- cyclic voltammetry (1)
- damage (1)
- dark ages, reionization, first stars (1)
- data behind figure (1)
- dielectric relaxation (1)
- dissociative electron attachment (1)
- dissoziative Elektronen Anlagerung (1)
- doctor-blade coating (1)
- double-layer (1)
- drug-delivery (1)
- dust, extinction (1)
- dynamic loading (1)
- dünne, flexible und formbare Schichten (1)
- electret stability (1)
- electrical chemotaxis assay (1)
- electricity consumption (1)
- electroanalysis (1)
- electromechanical transducers (sensors and actuators) (1)
- electron contact (1)
- electron-transport layers (1)
- elektrischer Chemotaxis Assy (1)
- elektromechanische Wandler (Sensoren und Aktoren) (1)
- energy losses (1)
- entrance test (1)
- epilepsy (1)
- exciton dynamics (1)
- ferroelectrets (1)
- ferromagnetism (1)
- field-effect transistor (1)
- film sensor (1)
- fluctuating surfaces (1)
- flussunterbrechende Analyse (1)
- fractal dimension (1)
- fullerene (1)
- galactic astronomy (1)
- galaktische Astrophysik (1)
- galaxies: abundances (1)
- galaxies: clusters: general (1)
- galaxies: formation (1)
- galaxies: fundamental parameters (1)
- galaxies: haloes (1)
- galaxies: individual (Large Magellanic Cloud, Small Magellanic Cloud) (1)
- galaxies: individual (RGB J2243+203) (1)
- galaxies: kinematics and dynamics (1)
- galaxies: statistics (1)
- galaxy (1)
- galaxy evolution (1)
- galaxy formation (1)
- gamma rays: ISM (1)
- gamma rays: stars (1)
- gamma-ray burst: general (1)
- gamma-ray burst: individual (GRB 170817A) (1)
- generational comparison (1)
- genetic networks (1)
- global jets (1)
- globular clusters: general (1)
- globular clusters: individual: NGC 6397 (1)
- glycerol oxidation (1)
- gold intercalation (1)
- granite (1)
- grating interferometry (1)
- gravitational waves (1)
- green solvents (1)
- group field theory (1)
- heat treatment (1)
- heatwaves (1)
- helical magnetic fields (1)
- high temperature (1)
- history and philosophy of astronomy (1)
- hybrid multi-junction solar cell (1)
- hybrid nanomaterials (1)
- hybride Mehrschichtsolarzellen (1)
- hydrogels (1)
- hysteresis (1)
- imaging (1)
- importance sampling (1)
- incoherent light (1)
- incoherent radiation (1)
- induced fit (1)
- induzierte Passform (1)
- inference (1)
- infrared: diffuse background (1)
- inner magnetosphere (1)
- ion migration (1)
- ionosphere interactions (1)
- jet stream (1)
- katalytische Isomerisation von Azobenzolen (1)
- kinematics (1)
- kinetic Alfven (1)
- kinetic instabilities (1)
- kink-like instability (1)
- kosmologische Simulationen (1)
- large area devices (1)
- laser illumination (1)
- lead halide perovskite (1)
- light emission (1)
- light management (1)
- line search (1)
- linear stability analysis (1)
- magnetische resonante Beugung (1)
- magnetischer Zirkulardichroismus (1)
- magnetoconvection (1)
- magnetohydrodynamics (1)
- magnetohydrodynamics (MHD) (1)
- magnetosome chains (1)
- magnetosonic (1)
- magnetosonic equatorial noise (1)
- magnetosphere (1)
- magnetostriction (1)
- magnetotactic bacteria (1)
- magnetotaktische Bakterien (1)
- massereiche Sterne (1)
- massive stars (1)
- material (1)
- mechanobiology (1)
- mesocrystals (1)
- metal nanoparticles (1)
- metal oxide (1)
- meteorological extremes (1)
- methods: data analysis (1)
- mock observations (1)
- models (1)
- modified electrode (1)
- molecule (1)
- motion of adsorbed nano-particles (1)
- motion registration (1)
- mutual information (1)
- nanoclusters (1)
- nanoparticles (1)
- neural synchonization (1)
- neutrinos (1)
- neutron diffraction (1)
- non-linear dynamics (1)
- nonequilibrium (1)
- nonlinear frequency conversion (1)
- nonlocal coupled oscillators (1)
- nudging (1)
- numerical techniques (1)
- numerische Methoden (1)
- opacity (1)
- open circuit voltage (1)
- optical simulations (1)
- optical spectroscopy (1)
- optically induced dynamics (1)
- optics (1)
- optisch induzierte Dynamik (1)
- organic (1)
- organische Solarzellen (1)
- outflows (1)
- outflows X-rays: binaries (1)
- oxygen quenching (1)
- particle-in-cell simulations (1)
- particles (1)
- peak load (1)
- peptides (1)
- periodically poled material (1)
- perovskite solar cell (1)
- perturbation approach (1)
- ph-responsive microgels (1)
- phase separation (1)
- phase transition (1)
- phonon (1)
- photoelectron spectroscopy (1)
- photoluminescence quenching (1)
- photon statistics (1)
- photoresponsive surfactants (1)
- physical activity (1)
- piezo-, pyro- and ferroelectricity (1)
- piezoelectret (1)
- planets and satellites: individual (Saturn) (1)
- planets and satellites: rings (1)
- plasmas (1)
- plasmasphere (1)
- plasmon nano-particles (1)
- plasmonic catalysis (1)
- plasmonische Katalyse (1)
- plasmonische Nanopartikeln (1)
- polarization (1)
- polarized radiation (1)
- poly(heptazine imide) (1)
- positioning (1)
- potential-energy surface (1)
- protein kinetics (1)
- protein-protein interaction (1)
- pulsars: individual: 4U0114+65 (1)
- pulsars: individual: rho Ophiuchi A (1)
- pump-probe experiment (1)
- quantum field theory (1)
- quantum gases (1)
- quartz crystal microbalance (1)
- quasi-free-standing graphene (1)
- quorum sensing (1)
- radio continuum: ISM (1)
- radio continuum: general (1)
- radio continuum: stars (1)
- raman-scattering (1)
- random search processes (1)
- rare earth (1)
- rare-earth metals (1)
- recognition (1)
- recollimation shocks (1)
- red giant stars (1)
- regional climate simulations (1)
- regionale Klimasimulationen (1)
- regular planar architecture (1)
- relativistic jets (1)
- relativistic processes (1)
- residual stress (1)
- ring current (1)
- rock (1)
- rote Riesensterne (1)
- sagittal X-ray diffraction (1)
- school (1)
- selective laser melting (1)
- self-sustained oscillations (1)
- seltene Erden (1)
- series (1)
- shock (1)
- solar wind dependence (1)
- spatial poisson distribution (1)
- spectrum (1)
- spin (1)
- spin-orbit interaction (1)
- split Hopkinson pressure bar (1)
- spontaneous emission (1)
- stability (1)
- stars: abundances (1)
- stars: chemically peculiar (1)
- stars: early type (1)
- stars: earlytype (1)
- stars: emission-line, Be (1)
- stars: fundamental parameters (1)
- stars: individual (AH Cep, CW Cep) (1)
- stars: individual (Cyg OB2 12) (1)
- stars: individual (HD 54879) (1)
- stars: individual: HR 7355 (1)
- stars: individual: R 145 (1)
- stars: individual: Rho Ophiuchi (1)
- stars: individual: WR 148 (1)
- stars: individual: gamma(2) Vel (1)
- stars: individual: red clump stars (1)
- stars: magnetic fields (1)
- stars: mass loss (1)
- stars: oscillations (1)
- starspots (1)
- states (1)
- stellar evolution (1)
- stellar population (1)
- stellar winds (1)
- stellare Population (1)
- stopped-flow (1)
- stratosphere (1)
- stratospheric polar vortex (1)
- structural properties (1)
- strukturelle Eigenschaften (1)
- subseasonal predictions (1)
- supergiants (1)
- superluminescent diodes (1)
- surface acoustic waves (1)
- surface cracks (1)
- surface modification (1)
- surveys (1)
- swelling behavior (1)
- synchrotron X-ray diffraction (1)
- synchrotron radiation (1)
- synoptic cyclones (1)
- synoptische Zyklone (1)
- synthetic extruded cordierite (1)
- synthetische Beobachtungen (1)
- techniques: spectroscopic (1)
- teleconnections (1)
- temperature (1)
- thermodynamic structure (1)
- thermodynamische Struktur (1)
- thickness insensitive active layers (1)
- thin flexible and conformable films (1)
- tissue engineering (1)
- titanium dioxide (1)
- tropical cyclones (1)
- turbulent transport (1)
- ultrafast (1)
- ultrafast phenomena (1)
- ultraschnelle Phänomene (1)
- unferring cellular networks (1)
- variables (1)
- voltage losses (1)
- vulnerability (1)
- water reduction reactions (1)
- water-vapor (1)
- waveguides (1)
- waves (1)
- wearable (1)
- winter circulation (1)
- x-ray diffraction (1)
- x-ray magnetic circular dichroism (XMCD) (1)
- x-ray magnetic resonant diffraction (XMRD) (1)
- youth (1)
- азобензолсодержащие ПАВ (1)
- каталитическая изомеризация азобензолов (1)
- плазмонные наночастицы (1)
- показатель преломления азобензолов (1)
Die Femtosekundendynamik nach resonanten Photoanregungen mit optischen und Röntgenpulsen ermöglicht eine selektive Verformung von chemischen N‐H‐ und N‐C‐Bindungen in 2‐Thiopyridon in wässriger Lösung. Die Untersuchung der orbitalspezifischen elektronischen Struktur und ihrer Dynamik auf ultrakurzen Zeitskalen mit resonanter inelastischer Röntgenstreuung an der N1s‐Resonanz am Synchrotron und dem Freie‐Elektronen‐Laser LCLS in Kombination mit quantenchemischen Multikonfigurationsberechnungen erbringen den direkten Nachweis dieser kontrollierten photoinduzierten Molekülverformungen und ihrer ultrakurzen Zeitskala.
Background: Inferring regulatory interactions between genes from transcriptomics time-resolved data, yielding reverse engineered gene regulatory networks, is of paramount importance to systems biology and bioinformatics studies. Accurate methods to address this problem can ultimately provide a deeper insight into the complexity, behavior, and functions of the underlying biological systems. However, the large number of interacting genes coupled with short and often noisy time-resolved read-outs of the system renders the reverse engineering a challenging task. Therefore, the development and assessment of methods which are computationally efficient, robust against noise, applicable to short time series data, and preferably capable of reconstructing the directionality of the regulatory interactions remains a pressing research problem with valuable applications.
Results: Here we perform the largest systematic analysis of a set of similarity measures and scoring schemes within the scope of the relevance network approach which are commonly used for gene regulatory network reconstruction from time series data. In addition, we define and analyze several novel measures and schemes which are particularly suitable for short transcriptomics time series. We also compare the considered 21 measures and 6 scoring schemes according to their ability to correctly reconstruct such networks from short time series data by calculating summary statistics based on the corresponding specificity and sensitivity. Our results demonstrate that rank and symbol based measures have the highest performance in inferring regulatory interactions. In addition, the proposed scoring scheme by asymmetric weighting has shown to be valuable in reducing the number of false positive interactions. On the other hand, Granger causality as well as information-theoretic measures, frequently used in inference of regulatory networks, show low performance on the short time series analyzed in this study.
Conclusions: Our study is intended to serve as a guide for choosing a particular combination of similarity measures and scoring schemes suitable for reconstruction of gene regulatory networks from short time series data. We show that further improvement of algorithms for reverse engineering can be obtained if one considers measures that are rooted in the study of symbolic dynamics or ranks, in contrast to the application of common similarity measures which do not consider the temporal character of the employed data. Moreover, we establish that the asymmetric weighting scoring scheme together with symbol based measures (for low noise level) and rank based measures (for high noise level) are the most suitable choices.
We investigate the heat transport through a rare earth multilayer system composed of yttrium (Y), dysprosium (Dy), and niobium (Nb) by ultrafast x-ray diffraction. This is an example of a complex heat flow problem on the nanoscale, where several different quasiparticles carry the heat and conserve a nonequilibrium for more than 10 ns. The Bragg peak positions of each layer represent layer-specific thermometers that measure the energy flow through the sample after excitation of the Y top layer with fs-laser pulses. In an experiment-based analytic solution to the nonequilibrium heat transport problem, we derive the individual contributions of the spins and the coupled electron-lattice system to the heat conduction. The full characterization of the spatiotemporal energy flow at different starting temperatures reveals that the spin excitations of antiferromagnetic Dy speed up the heat transport into the Dy layer at low temperatures, whereas the heat transport through this layer and further into the Y and Nb layers underneath is slowed down. The experimental findings are compared to the solution of the heat equation using macroscopic temperature-dependent material parameters without separation of spin and phonon contributions to the heat. We explain why the simulated energy density matches our experiment-based derivation of the heat transport, although the simulated thermoelastic strain in this simulation is not even in qualitative agreement.
The femtosecond excited-state dynamics following resonant photoexcitation enable the selective deformation of N-H and N-C chemical bonds in 2-thiopyridone in aqueous solution with optical or X-ray pulses. In combination with multiconfigurational quantum-chemical calculations, the orbital-specific electronic structure and its ultrafast dynamics accessed with resonant inelastic X-ray scattering at the N 1s level using synchrotron radiation and the soft X-ray free-electron laser LCLS provide direct evidence for this controlled photoinduced molecular deformation and its ultrashort time-scale.
The femtosecond excited-state dynamics following resonant photoexcitation enable the selective deformation of N-H and N-C chemical bonds in 2-thiopyridone in aqueous solution with optical or X-ray pulses. In combination with multiconfigurational quantum-chemical calculations, the orbital-specific electronic structure and its ultrafast dynamics accessed with resonant inelastic X-ray scattering at the N 1s level using synchrotron radiation and the soft X-ray free-electron laser LCLS provide direct evidence for this controlled photoinduced molecular deformation and its ultrashort time-scale.
We report on the nonequilibrium dynamics of the electronic structure of the layered semiconductor Ta2NiSe5 investigated by time-and angle-resolved photoelectron spectroscopy. We show that below the critical excitation density of F-C = 0.2 mJ cm(-2), the band gap narrows transiently, while it is enhanced above FC. Hartree-Fock calculations reveal that this effect can be explained by the presence of the low-temperature excitonic insulator phase of Ta2NiSe5, whose order parameter is connected to the gap size. This work demonstrates the ability to manipulate the band gap of Ta2NiSe5 with light on the femtosecond time scale.
Ultrafast and Energy-Efficient Quenching of Spin Order: Antiferromagnetism Beats Ferromagnetism
(2017)
By comparing femtosecond laser pulse induced ferro- and antiferromagnetic dynamics in one and the same material-metallic dysprosium-we show both to behave fundamentally different. Antiferromagnetic order is considerably faster and much more efficiently reduced by optical excitation than its ferromagnetic counterpart. We assign the fast and extremely efficient process in the antiferromagnet to an interatomic transfer of angular momentum within the spin system. Our findings imply that this angular momentum transfer channel is effective in other magnetic metals with nonparallel spin alignment. They also point out a possible route towards energy-efficient spin manipulation for magnetic devices.
We develop a simple two-zone interpretation of the broadband baseline Crab nebula spectrum between 10(-5) eV and similar to 100 TeV by using two distinct log-parabola energetic electrons distributions. We determine analytically the very-high energy photon spectrum as originated by inverse-Compton scattering of the far-infrared soft ambient photons within the nebula off a first population of electrons energized at the nebula termination shock. The broad and flat 200 GeV peak jointly observed by Fermi/LAT and MAGIC is naturally reproduced. The synchrotron radiation from a second energetic electron population explains the spectrum from the radio range up to similar to 10 keV. We infer from observations the energy dependence of the microscopic probability of remaining in proximity of the shock of the accelerating electrons.
The recent development of donor–acceptor copolymers has led to an enormous improvement in the performance of organic solar cells and organic field-effect transistors. Here we describe the synthesis, detailed characterisation, and application of a series of structurally modified copolymers to investigate fundamental structure–property relationships in this class of conjugated polymers. The interplay between chemical structure and optoelectronic properties is investigated. These are further correlated to the charge transport and solar cell performance, which allows us to link their chemical structure to the observed physical properties.
The presence of a low-to mid-latitude interhemispheric hydrologic seesaw is apparent over orbital and glacial-interglacial timescales, but its existence over the most recent past remains unclear. Here we investigate, based on climate proxy reconstructions from both hemispheres, the inter-hemispherical phasing of the Intertropical Convergence Zone (ITCZ) and the low-to mid-latitude teleconnections in the Northern Hemisphere over the past 2000 years. A clear feature is a persistent southward shift of the ITCZ during the Little Ice Age until the beginning of the 19th Century. Strong covariation between our new composite ITCZ-stack and North Atlantic Oscillation (NAO) records reveals a tight coupling between these two synoptic weather and climate phenomena over decadal-to-centennial timescales. This relationship becomes most apparent when comparing two precisely dated, high-resolution paleorainfall records from Belize and Scotland, indicating that the low-to mid-latitude teleconnection was also active over annual-decadal timescales. It is likely a combination of external forcing, i.e., solar and volcanic, and internal feedbacks, that drives the synchronous ITCZ and NAO shifts via energy flux perturbations in the tropics.