A5057576274- Organic Electronics and Photovoltaics
- Laser-Matter Interactions and Applications
- Advanced Fluorescence Microscopy Techniques
- Luminescence and Fluorescent Materials
- Molecular Junctions and Nanostructures
- Advanced Electron Microscopy Techniques and Applications
- Photochemistry and Electron Transfer Studies
- Conducting polymers and applications
- Spectroscopy and Quantum Chemical Studies
- Mass Spectrometry Techniques and Applications
- Plasmonic and Surface Plasmon Research
- Organic Light-Emitting Diodes Research
- Near-Field Optical Microscopy
- Perovskite Materials and Applications
- Advanced biosensing and bioanalysis techniques
- Advanced Fiber Laser Technologies
- Photoreceptor and optogenetics research
- Advanced Chemical Physics Studies
- Force Microscopy Techniques and Applications
- Gold and Silver Nanoparticles Synthesis and Applications
- Quantum Dots Synthesis And Properties
- Atomic and Molecular Physics
- Laser-Plasma Interactions and Diagnostics
- Ion-surface interactions and analysis
- RNA Interference and Gene Delivery
Lund University
2019-2023
University of Regensburg
2014-2023
Carl von Ossietzky Universität Oldenburg
2013-2023
Max Planck Institute of Quantum Optics
2013-2021
Skåne University Hospital
2021
HUN-REN Wigner Research Centre for Physics
2020
ELI-HU Research and Development Non-Profit
2020
Center for NanoScience
2008-2019
Ludwig-Maximilians-Universität München
2007-2019
Institut für Technische und Angewandte Physik (Germany)
2016-2018
Proton Still Too Small Despite a proton's tiny size, it is possible to measure its radius based on charge or magnetization distributions. Traditional measurements of proton were the scattering between protons and electrons. Recently, precision measurement line in spectrum muonium—an atom consisting muon, instead an electron—revealed inconsistent with that deduced from studies. Antognini et al. (p. 417 ; see Perspective by Margolis ) examined different spectral muonium, results less dependent...
On the ROXS: Photobleaching represents one of main limitations modern fluorescence microscopy. A reducing and oxidizing system (ROXS) has been introduced that recovers triplet states as well charge-separated through electron-transfer reactions (see picture). Thus blinking photobleaching fluorophores is strikingly reduced.
Recent advances in photobleaching and blinking prevention have aided the advancement of single-molecule super-resolution fluorescence microscopy. However, a common mechanism action antifading agents such as Trolox is still missing. In this communication we present evidence that acts accordance with involves triplet quenching through electron transfer subsequent recovery resulting radical ion by complementary redox reaction. The required oxidant for unifying based on reducing oxidizing system...
When electromagnetic fields impinge on nanoscale structured materials, optical field concentrations can occur that enhance the strength up to 2 orders of magnitude. The strong-field interaction physics enabled by these nano-optical building blocks probes highly nonlinear phenomena pave way toward unique matter such as ultrafast electron imaging and spectroscopy ultrahigh frequency transistor concepts are preludes light-wave electronics. This article reviews fundamentals applications phenomena.
Fluorescent molecular switches have widespread potential for use as sensors, material applications in electro-optical data storages and displays, superresolution fluorescence microscopy. We demonstrate that adjustment of fluorophore properties environmental conditions allows the ordinary fluorescent dyes efficient single-molecule report sensitively on their local redox condition. Adding or removing reductant oxidant, oxazine between stable nonfluorescent states. At low oxygen concentrations,...
New concepts for superresolution fluorescence microscopy by subsequent localization of single molecules using photoswitchable or photoactivatable fluorophores are rapidly emerging and provide new ways to resolve structures beyond the diffraction limit. Here, we demonstrate that imaging can be carried out with practically every single-molecule compatible, synthetic fluorophore controlling their emission properties. We prepare dark states removing oxygen extends triplet state lifetime several...
We report photoelectron emission from the apex of a sharp gold nanotaper illuminated via grating coupling at distance 50 μm site with few-cycle near-infrared laser pulses. find fifty-fold increase in electron yield over that for direct illumination. Spatial localization to nanometer-sized region is demonstrated by point-projection microscopic imaging silver nanowire. Our results reveal negligible plasmon-induced taper shaft and thus efficient nanofocusing plasmon wavepackets. This novel,...
The aggregation of conjugated polymers and electronic coupling chromophores play a central role in the fundamental understanding light charge generation processes. Here we report that predominant isolated aggregates can be switched reversibly between H-type J-type by partially swelling drying aggregates. Aggregation is identified shifts photoluminescence energy, changes vibronic peak ratio, lifetime. This experiment unravels internal structure aggregate highlights importance process final...
Abstract The energy levels of hydrogen-like atomic systems can be calculated with great precision. Starting from their quantum mechanical solution, they have been refined over the years to include electron spin, relativistic and field effects, tiny shifts related complex structure nucleus. These caused by nuclear are vastly magnified in formed a negative muon nucleus, so spectroscopy these muonic ions used investigate high Here we present measurement two 2S–2P transitions helium-4 ion that...
An inside job: By using single-molecule spectroscopy (SMS) several effects of solvent vapor induced annealing (SVA) were studied directly on single conjugated polymers, e.g.: SVA-induced translocations, folding/unfolding dynamics, and changes in the morphological order. It is shown that chains can be trapped by spin-coating a disordered conformation subsequent SVA leads to an equilibrated, highly ordered (see picture). Detailed facts importance specialist readers are published as "Supporting...
Significance Ideal photovoltaic cells would be black, absorbing all of the Sun’s radiation, whereas Nature’s machinery for solar energy harvesting—photosynthesis—looks green. Organic semiconductor devices, based on molecular building blocks, lie conceptionally between extremes inorganic and photosynthetic light harvesting. How can organic appear almost black if they are units? Using single-molecule spectroscopy, we identify fundamental electronic blocks reveal that discrete molecule-like...
Control of chain length and morphology in combination with single-molecule spectroscopy techniques provides a comprehensive photophysical picture excited-state losses the prototypical conjugated polymer poly(3-hexylthiophene) (P3HT). Our examination reveals universal self-quenching mechanism, based on singlet-triplet exciton annihilation, which accounts for dramatic loss fluorescence quantum yield single P3HT between its solution (unfolded) bulklike (folded) state. Triplet excitons...
Significance In most optics textbooks, one writes the electric field describing an optical wave as a product of temporal and spatial amplitudes. This approximation often breaks down for short pulses. An example such spatiotemporal coupling is chromatic aberrations, where focal properties radiation vary with frequency over pulse bandwidth. this work, we point out significant aberrations attosecond pulses, which depend on geometry generation process. These are intrinsic to process need be...
Abstract The integration of metallic plasmonic nanoantennas with quantum emitters can dramatically enhance coherent harmonic generation, often resulting from the coupling fundamental fields to higher-energy, electronic or excitonic transitions emitters. ultrafast optical dynamics such hybrid plasmon–emitter systems have rarely been explored. Here, we study those by interferometrically probing nonlinear emission individual porous gold nanosponges infiltrated zinc oxide (ZnO) Few-femtosecond...
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In this paper we experimentally combine a recently developed AFM-based molecule-by-molecule assembly (single-molecule cut-and-paste, SMCP) with subdiffraction resolution fluorescence imaging. Using "Blink-Microscopy", which exploits the fluctuating emission of single molecules for reconstruction superresolution images, resolved SMCP assembled structures features below diffraction limit. Artificial line patterns then served as calibration to characterize parameters, such labeling density,...
Photocatalytic dehalogenation by a common dyestuff under aqueous conditions is driven energy-additive absorption of two photons on the single-molecule level.
An ideal point light source is as small and bright possible. For fluorescent sources, homogeneity of the sources important well that units inside maintain their photophysical properties, which compromised by dye aggregation. Here we propose DNA origami a rigid scaffold to arrange molecules in dense pixel array with high control stoichiometry dye–dye interactions. In order find highest labeling density structure without influencing photophysics, alter distance two ATTO647N dyes single base...
Hot electron relaxation and transport in nanostructures involve a multitude of ultrafast processes whose interplay relative importance are still not fully understood, but which relevant for future applications areas such as photocatalysis optoelectronics. To unravel these processes, their dynamics both time space must be studied with high spatiotemporal resolution structurally well-defined nanoscale objects. We employ time-resolved photoemission microscopy to image the photogenerated hot...
An appealing definition of the term "molecule" arises from consideration nature fluorescence, with discrete molecular entities emitting a stream single photons. We address question how large object may become by growing deterministic aggregates conjugated polymer chains. Even particles containing dozens individual chains still behave as quantum emitters due to efficient excitation energy transfer, whereas brightness is raised increased absorption cross-section suprastructure. Excitation can...