Jochen Küpper
YOU?
Author Swipe
View article: Visualizing the strong field–induced molecular breakup of C <sub>60</sub> via x-ray diffraction
Visualizing the strong field–induced molecular breakup of C <sub>60</sub> via x-ray diffraction Open
Laser-driven dynamics in polyatomic molecules poses a complex many-body problem. Understanding intense light-matter interaction is crucial for steering intramolecular quantum dynamical processes. Here, we record time-resolved x-ray diffrac…
View article: Direct Observation of the Exciton-Polaron in Single CsPbBr<sub>3</sub> Quantum Dots
Direct Observation of the Exciton-Polaron in Single CsPbBr<sub>3</sub> Quantum Dots Open
The Outstanding optoelectronic properties of lead halide perovskites have been related to the formation of polarons. Nevertheless, the observation of the atomistic deformation brought about by one electron-hole pair in these materials has …
View article: Controlling rovibrational state populations of polar molecules in inhomogeneous electric fields of the Stark deceleration: molecular dynamics and quantum chemistry simulations
Controlling rovibrational state populations of polar molecules in inhomogeneous electric fields of the Stark deceleration: molecular dynamics and quantum chemistry simulations Open
We propose a modified Stark-chirped rapid adiabatic passage technique for a robust rovibrational population transfer in the gas phase molecules in the presence of certain inhomogeneous electric fields. As an example application, the new st…
View article: Computing Excited States of Molecules Using Normalizing Flows
Computing Excited States of Molecules Using Normalizing Flows Open
Calculations of highly excited and delocalized molecular vibrational states are computationally challenging tasks, which strongly depend on the choice of coordinates for describing vibrational motions. We introduce a new method that levera…
View article: An improved simulation methodology for nanoparticle injection through aerodynamic lens systems
An improved simulation methodology for nanoparticle injection through aerodynamic lens systems Open
Aerosol injectors applied in single-particle diffractive imaging experiments demonstrated their potential in efficiently delivering nanoparticles with high density. Continuous optimization of injector design is crucial for achieving high-d…
View article: Direct observation of the exciton polaron by serial femtosecond crystallography on single CsPbBr$_3$ quantum dots
Direct observation of the exciton polaron by serial femtosecond crystallography on single CsPbBr$_3$ quantum dots Open
The outstanding opto-electronic properties of lead halide perovskites have been related to the formation of polarons. Nevertheless, the observation of the atomistic deformation brought about by one electron-hole pair in these materials has…
View article: Laser-Induced Alignment of Nanoparticles and Macromolecules for Coherent-Diffractive-Imaging Applications
Laser-Induced Alignment of Nanoparticles and Macromolecules for Coherent-Diffractive-Imaging Applications Open
Laser-induced alignment of particles and molecules was long envisioned to support three-dimensional structure determination using "single-molecule diffraction" with X-ray free-electron lasers [PRL 92, 198102 (2004)]. However, the alignment…
View article: A versatile and transportable endstation for controlled molecule experiments
A versatile and transportable endstation for controlled molecule experiments Open
We report on a new versatile transportable endstation for controlled molecule (eCOMO) experiments providing a combination of molecular beam purification by electrostatic deflection and simultaneous ion and electron detection using velocity…
View article: Timepix3: single-pixel multi-hit energy-measurement behaviour
Timepix3: single-pixel multi-hit energy-measurement behaviour Open
The event-driven hybrid-pixel detector readout chip, Timepix3, has the ability to simultaneously measure the time of an event on the nanosecond timescale and the energy deposited in the sensor. However, the behaviour of the system when two…
View article: Learning phase-space flows using time-discrete implicit Runge-Kutta PINNs
Learning phase-space flows using time-discrete implicit Runge-Kutta PINNs Open
We present a computational framework for obtaining multidimensional phase-space solutions of systems of non-linear coupled differential equations, using high-order implicit Runge-Kutta Physics- Informed Neural Networks (IRK-PINNs) schemes.…
View article: Molecular influence on nuclear-quadrupole-coupling effects in laser induced alignment
Molecular influence on nuclear-quadrupole-coupling effects in laser induced alignment Open
We studied the effect of nuclear-quadrupole interactions on the field-free impulsive alignment of different asymmetric-top molecules. Our analysis is focused on the influence of the hyperfine- and rotational-energy-level structures. These …
View article: Observation of Aerosolization-induced Morphological Changes in Viral Capsids
Observation of Aerosolization-induced Morphological Changes in Viral Capsids Open
Single-stranded RNA viruses co-assemble their capsid with the genome and variations in capsid structures can have significant functional relevance. In particular, viruses need to respond to a dehydrating environment to prevent genomic degr…
View article: Resolving Nonequilibrium Shape Variations among Millions of Gold Nanoparticles
Resolving Nonequilibrium Shape Variations among Millions of Gold Nanoparticles Open
Nanoparticles, exhibiting functionally relevant structural heterogeneity, are at the forefront of cutting-edge research. Now, high-throughput single-particle imaging (SPI) with X-ray free-electron lasers (XFELs) creates opportunities for r…
View article: Controlled molecule injector for cold, dense, and pure molecular beams at the European x-ray free-electron laser
Controlled molecule injector for cold, dense, and pure molecular beams at the European x-ray free-electron laser Open
A permanently available molecular-beam injection setup for controlled molecules (COMO) was installed and commissioned at the small quantum systems (SQS) instrument at the European x-ray free-electron laser (EuXFEL). A $b$-type electrostati…
View article: Ultrafast dynamics of fluorene initiated by highly intense laser fields
Ultrafast dynamics of fluorene initiated by highly intense laser fields Open
We present an investigation of the ultrafast dynamics of the polycyclic aromatic hydrocarbon fluorene initiated by an intense femtosecond near- infrared laser pulse (810 nm) and probed by a weak visible pulse (405 nm). Using a multichannel…
View article: Timepix3: single-pixel multi-hit energy-measurement behavior
Timepix3: single-pixel multi-hit energy-measurement behavior Open
The event-driven hybrid-pixel detector readout chip, Timepix3, has the ability to simultaneously measure the time of an event on the nanosecond timescale and the energy deposited in the sensor. However, the behaviour of the system when two…
View article: Reaction Pathways of Water Dimer Following Single Ionization
Reaction Pathways of Water Dimer Following Single Ionization Open
Water dimer (H2O)2─a vital component of the earth's atmosphere─is an important prototypical hydrogen-bonded system. It provides direct insights into fundamental chemical and biochemical processes, e.g., proton transfer and ionic supramolec…
View article: Ultrafast dynamics of fluorene initiated by highly intense laser fields
Ultrafast dynamics of fluorene initiated by highly intense laser fields Open
We present an investigation of the ultrafast dynamics of the polycyclic aromatic hydrocarbon fluorene initiated by an intense femtosecond near- infrared laser pulse (810 nm) and probed by a weak visible pulse (405 nm). Using a multichannel…
View article: Resolving non-equilibrium shape variations amongst millions of gold nanoparticles
Resolving non-equilibrium shape variations amongst millions of gold nanoparticles Open
Nanoparticles, exhibiting functionally relevant structural heterogeneity, are at the forefront of cutting-edge research. Now, high-throughput single-particle imaging (SPI) with x-ray free-electron lasers (XFELs) creates unprecedented oppor…
View article: Water is a radiation protection agent for ionised pyrrole
Water is a radiation protection agent for ionised pyrrole Open
Radiation-induced damage of biological matter is an ubiquitous problem in nature. The influence of the hydration environment is widely discussed, but its exact role remains elusive. Utilising well defined solvated-molecule aggregates, we e…
View article: Accuracy and Performance Evaluation of Low Density Internal and External Flow Predictions using CFD and DSMC
Accuracy and Performance Evaluation of Low Density Internal and External Flow Predictions using CFD and DSMC Open
The Direct Simulation Monte Carlo (DSMC) method was widely used to simulate low density gas flows with large Knudsen numbers. However, DSMC encounters limitations in the regime of lower Knudsen numbers (Kn<0.1). In such cases, approaches f…
View article: A versatile and transportable endstation for controlled molecule experiments
A versatile and transportable endstation for controlled molecule experiments Open
We report on a new versatile transportable endstation for controlled molecule (eCOMO) experiments providing a combination of molecular beam purification by electrostatic deflection and simultaneous ion and electron detection using velocity…
View article: Ultrafast dynamics of fluorene initiated by highly intense laser fields
Ultrafast dynamics of fluorene initiated by highly intense laser fields Open
We present an investigation of the ultrafast dynamics of the polycyclic aromatic hydrocarbon fluorene initiated by an intense femtosecond near-infrared laser pulse (810 nm) and probed by a weak visible pulse (405 nm).
View article: 3D diffractive imaging of nanoparticle ensembles using an x-ray laser
3D diffractive imaging of nanoparticle ensembles using an x-ray laser Open
Please check the README.md file for more information about the dataset.
View article: Specific versus Nonspecific Solvent Interactions of a Biomolecule in Water
Specific versus Nonspecific Solvent Interactions of a Biomolecule in Water Open
Solvent interactions, particularly hydration, are vital in chemical and biochemical systems. Model systems reveal microscopic details of such interactions. We uncover a specific hydrogen-bonding motif of the biomolecular building block ind…
View article: Unraveling the ultrafast dynamics of thermal-energy chemical reactions
Unraveling the ultrafast dynamics of thermal-energy chemical reactions Open
We discuss how one can initiate, image, and disentangle the ultrafast elementary steps of thermal-energy chemical dynamics, building on advances in controlling molecules, producing ultrashort mid-infrared pulses, and frontier imaging techn…
View article: New aerodynamic lens injector for single particle diffractive imaging
New aerodynamic lens injector for single particle diffractive imaging Open
Contains fulltext : 312063.pdf (Publisher’s version ) (Open Access)