A5001715181- Spectroscopy and Quantum Chemical Studies
- Strong Light-Matter Interactions
- Perovskite Materials and Applications
- Quantum and electron transport phenomena
- Semiconductor Quantum Structures and Devices
- Molecular Junctions and Nanostructures
- Quantum optics and atomic interactions
- Plasmonic and Surface Plasmon Research
- Spectroscopy and Laser Applications
- Photoreceptor and optogenetics research
- Quantum Dots Synthesis And Properties
- Chalcogenide Semiconductor Thin Films
- Fullerene Chemistry and Applications
- Plant and animal studies
- Advanced Fiber Laser Technologies
- Island Studies and Pacific Affairs
- Asian Geopolitics and Ethnography
- Eurasian Exchange Networks
- Australian History and Society
- Solid-state spectroscopy and crystallography
- Insect and Pesticide Research
- Quantum Information and Cryptography
- Photochemistry and Electron Transfer Studies
- Laser-Matter Interactions and Applications
- Optical properties and cooling technologies in crystalline materials
Carl von Ossietzky Universität Oldenburg
2017-2025
Transition metal dichalcogenides (TMDs) are quantum confined systems with interesting optoelectronic properties, governed by Coulomb interactions in the monolayer (1L) limit, where strongly bound excitons provide a sensitive probe for many-body interactions. Here, we use two-dimensional electronic spectroscopy (2DES) to investigate and their dynamics 1L-WS
The primary step in the elusive ability of migratory birds to sense weak Earth-strength magnetic fields is supposedly light-induced formation a long-lived, magnetically sensitive radical pair inside cryptochrome flavoprotein located retina these birds. Blue light absorption by flavin chromophore triggers series sequential electron transfer steps across tetradic tryptophan chain towards acceptor. recent express 4 from night-migratory European robin (Erithacus rubecula), ErCry4, and replace...
Abstract Coupling electromagnetic radiation with matter, e.g., by resonant light fields in external optical cavities, is highly promising for tailoring the optoelectronic properties of functional materials on nanoscale. Here, we demonstrate that even internal induced coherent lattice motions can be used to control transient excitonic response CsPbBr 3 halide perovskite crystals. Upon photoexcitation, two-dimensional electronic spectroscopy reveals an peak structure oscillating persistently a...
Two-dimensional electronic spectroscopy (2DES) is a powerful method to study coherent and incoherent interactions dynamics in complex quantum systems by correlating excitation detection energies nonlinear experiment. Such can be probed with time resolution limited only the duration of employed laser pulses spectral range defined pulse spectrum. In blue (<500 nm), generation sufficiently broadband ultrashort durations 10 fs or less has been challenging so far. Here, we present 2DES setup...
Since its introduction almost three decades ago, two-dimensional electronic spectroscopy (2DES) has evolved into a mature and powerful technique to reveal the inner workings of quantum systems with high temporal spectral resolution. In general, this can isolate different contributions nonlinear response provides access dynamical pathways system evolution. Such isolation be achieved in experimental geometries. original, fully noncollinear implementation, directional phase matching allows for...
We apply ultrafast polarization shaping to an ultrabroadband carrier envelope phase (CEP) stable white light supercontinuum generate polarization-tailored bichromatic laser fields of low-order frequency ratio. The generation orthogonal linearly and counter-rotating circularly polarized is achieved by introducing a composite polarizer in the Fourier plane 4 f shaper. resulting Lissajous- propeller-type profiles are characterized experimentally cross-correlation trajectories. scheme provides...
Enlarging exciton coherence lengths in molecular aggregates is critical for enhancing the collective optical and transport properties of thin film nanostructures or devices. We demonstrate that length squaraine can be increased from 10 to 24 units at room temperature when preparing aggregated on a metallic rather than dielectric substrate. Two-dimensional electronic spectroscopy measurements reveal much lower degree inhomogeneous line broadening gold film, pointing reduced disorder. The...
Squaraines are prototypical quadrupolar charge-transfer chromophores that have recently attracted much attention as building blocks for solution-processed photovoltaics, fluorescent probes with large two-photon absorption cross sections, and aggregates circular dichroism. Their optical properties often rationalized in terms of phenomenological essential state models, considering the coupling two zwitterionic excited states to a neutral ground state. As result, transitions lowest S1...
Halide perovskites are promising optoelectronic materials. Despite impressive device performance, especially in photovoltaics, the femtosecond dynamics of elementary optical excitations and their interactions still debated. Here we combine ultrafast two-dimensional electronic spectroscopy (2DES) semiconductor Bloch equations (SBEs) to probe room-temperature nonequilibrium CsPbBr3 crystals. Experimentally, distinguish between excitonic free-carrier transitions, extracting a ∼30 meV exciton...
In recent years, research has emphasized the significant influence of vibronic couplings on charge separation in donor–acceptor molecules and thin films. Diaminoterephthalates (DATs), known for their versatile optical electronic properties, are intriguing donor materials. Efficient, vibronically assisted DAT-acceptor dyads been suggested. This study therefore investigates dynamics DAT-linker-fullerene a polar solvent by using transient absorption spectroscopy. The results demonstrate...
The coherent coupling between electronic excitations and vibrational modes of molecules largely affects the optical charge transport properties organic semiconductors molecular solids. To analyze these couplings by means ultrafast spectroscopy, highly ordered crystalline films with large domains are particularly suitable because can be addressed individually, hence allowing azimuthal polarization-resolved measurements. Impressive examples this thin perfluoropentacene (PFP) molecules, which...
Ultrafast spectroscopy provides unique access to the coherent dynamics of atomic, molecular, and solid state quantum systems. A most powerful, yet experimentally challenging tool for this is two-dimensional electronic (2DES), allowing isolate excitation pathways selectively probe incoherent couplings by controlling phase ultrashort pulses that interact with system. Its experimental implementation can in principle greatly be simplified employing inherently stable birefringent in-line...
The strong coherent coupling of quantum emitters to vacuum fluctuations the light field offers opportunities for manipulating optical and transport properties nanomaterials, with potential applications ranging from ultrasensitive all-optical switching creating polariton condensates. Often, ubiquitous decoherence processes at ambient conditions limit these couplings such short time scales that dynamics interacting system remains elusive. Prominent examples are strongly coupled exciton-plasmon...
Selecting distinct quantum pathways in two-dimensional electronic spectroscopy (2DES) can give particularly deep insights into coherent and incoherent interactions dynamics various materials. This includes isolating rephasing non-rephasing for conventional single-quantum 2DES, but also the ability to record double- zero-quantum spectra. Such advanced 2DES schemes usually require phase-cycling when performed a partially or fully collinear geometry. A simple effective implementation of...
Selecting distinct quantum pathways in two-dimensional electronic spectroscopy (2DES) can give particularly deep insights into coherent and incoherent interactions dynamics various materials. This includes isolating rephasing non-rephasing for conventional single-quantum 2DES, but also the ability to record double- zero-quantum spectra. Such advanced 2DES schemes usually require phase-cycling when performed a partially or fully collinear geometry. A simple effective implementation of...
Selecting distinct quantum pathways in two-dimensional electronic spectroscopy (2DES) can give particularly deep insights into coherent and incoherent interactions dynamics various materials. This includes isolating rephasing non-rephasing for conventional single-quantum 2DES, but also the ability to record double- zero-quantum spectra. Such advanced 2DES schemes usually require phase-cycling when performed a partially or fully collinear geometry. A simple effective implementation of...
This chapter discusses recent experimental work exploring the optical properties and quantum dynamics of organic semiconductor nanostructures based on squaraine dyes. Squaraines are prototypical quadrupolar charge-transfer chromophores interest for solu-tion-processed photovoltaics as aggregates with large circular dichroism. Here, we demonstrate exploit their unique emitters implementing hy-brid featuring strong exciton-plasmon couplings. We show that unusual electronic squaraines result in...
Strong exciton-plasmon-couplings are investigated using two-dimensional electronic spectroscopy, revealing Rabi oscillations of polariton cross-peaks and accessing two-quantum excitations. Coherent population between excitons that strongly weakly coupled to the plasmonic field demonstrated.
Halide perovskites (HaPs) have rapidly grown as highly promising photovoltaic materials. Despite the impressive device efficiencies, however, fundamental mechanisms governing their unusual optoelectronic properties are still unclear [1]. In particular, nature of elementary optical excitations, dynamics and interactions on ultrafast timescales currently debated. Due to comparatively low exciton binding energy, typically <; 50 meV[2], near-bandgap absorption in HaPs is a mixture excitons free...
We track ultrafast charge carrier relaxation and the concurrent build-up of dynamical exciton screening on a 30-fs timescale, probe strong electron-phonon couplings in halide perovskite crystals by temperature-dependent two-dimensional electronic spectroscopy.
The primary step in the elusive ability of migratory birds to sense weak Earth-strength magnetic fields is supposedly light-induced formation a long-lived, magnetically sensitive radical pair inside cryptochrome flavoprotein located retina these birds. Blue light absorption by flavin chromophore triggers series sequential electron transfer steps across tetradic tryptophan chain towards acceptor. recent express 4 from night-migratory European robin (Erithacus rubecula), ErCry4, and replace...
We explore dynamics of strong exciton-plasmon couplings using two-dimensional electronic spectra displaying pronounced Rabi oscillations their cross-peaks. Radiative govern the polariton nonlinearity and provide first access to two-quantum-excitations coupled system.