A5023259632- Laser-Matter Interactions and Applications
- Advanced Chemical Physics Studies
- Mass Spectrometry Techniques and Applications
- Spectroscopy and Quantum Chemical Studies
- Polynomial and algebraic computation
- Matrix Theory and Algorithms
- Cold Atom Physics and Bose-Einstein Condensates
- Advanced Fiber Laser Technologies
- Nonlinear Photonic Systems
- Quantum chaos and dynamical systems
- Numerical Methods and Algorithms
- Atomic and Molecular Physics
- Photochemistry and Electron Transfer Studies
- Spectroscopy and Laser Applications
- Photonic and Optical Devices
- Quantum optics and atomic interactions
- Advanced Numerical Methods in Computational Mathematics
- Laser-Plasma Interactions and Diagnostics
- Spectroscopy Techniques in Biomedical and Chemical Research
- Lanthanide and Transition Metal Complexes
- Chaos control and synchronization
- Random lasers and scattering media
Max-Born-Institute for Nonlinear Optics and Short Pulse Spectroscopy
2013-2019
Fritz Haber Institute of the Max Planck Society
2017-2019
King Abdullah University of Science and Technology
2012-2013
Public Risk Management Association
2012-2013
HealthInsight
2012
High harmonic generation (HHG) spectroscopy has opened up a new frontier in ultrafast science, where electronic dynamics can be measured on an attosecond time scale. The strong laser field that triggers the high response also opens multiple quantum pathways for multielectron molecules, resulting complex process of rearrangement during ionization. Using combined experimental and theoretical approaches, we show how multi-dimensional HHG used to detect follow core sub-laser cycle scales. We...
We present a new extension of the UKRmol electron–molecule scattering code suite, which allows one to compute ab initio photoionization and photorecombination amplitudes for complex molecules, resolved both on molecular alignment (orientation) emission angle energy photoelectron. illustrate our approach using CO2 as an example, analyze importance multi-channel effects by performing calculations at different, increasing levels complexity. benchmark method comparing results with experimental...
We present measurements of photoelectron angular distributions (PADs) for the ionization aligned CO2 molecules by an extreme ultraviolet laser pulse (17–45 eV) that is produced via high-harmonic generation, and polarized perpendicularly to alignment axis. Differential PADs are recorded taking difference between two anti-aligned molecules. The results compared with ab initio multi-channel R-matrix calculations, which extended include computation PADs. calculations agree very well experiment,...
We present the first ab initio photoionization calculations for NO2 molecule in its equilibrium geometry using multichannel R- matrix method and a multiconfigurational description of system. focus on role correlation find that it plays key role, both at level partial cross sections asymmetry parameters. For most sophisticated model used here, we achieve excellent agreement with experimental data Baltzer et al (2009 Chem. Phys. 237 451–70 ) parameters angle-resolved photo-electron spectra....
Quantemol-N is an expert system designed to run the widely used UK Molecular R-matrix code (UKRMol). Originally consider electron–molecule collision problems, here we present extension treat molecular photoionization. Sample results are given for photoionization of nitrogen and methane. Comparisons made with experimental showing good agreement.
We present the first <italic>ab initio</italic> multi-channel photoionization calculations for NO<sub>2</sub> in vicinity of <sup>2</sup>A<sub>1</sub>/<sup>2</sup>B<sub>2</sub> conical intersection, a range nuclear geometries, using our newly developed set tools based on multichannel <italic>R</italic>-matrix method.
Time-resolving and controlling coupled electronic nuclear dynamics at conical intersections on the sub-femtosecond to few-femtosecond time scale is among challenging goals of attosecond physics. Here we present numerical simulations time-resolved photoelectron spectroscopy such in NO2, where electron-nuclear motion 2A1/2B2 intersection steered sub-laser-cycle by a nearly single-cycle, waveform controlled mid-infrared laser pulse. For rigorous description photoionization dynamics, employ ab...
Abstract By employing a nonlinear quantum kicked rotor model, we investigate the transport of energy in multidimensional chaos. This problem has profound implications many fields science ranging from Anderson localization to time reversal classical and waves. We begin our analysis with series parallel numerical simulations, whose results show an unexpected anomalous behavior. tackle by fully analytical approach characterized Lie groups solitons theory, demonstrating existence universal,...
We investigate the influence of attosecond electron dynamics photoionization on femtosecond fragmentation molecular ion left behind. consider dissociative ${\mathrm{N}}_{2}$ molecule, induced by an extreme-ultraviolet (XUV) pulse in presence a moderately strong infrared (IR) laser field. show that kinetic energy spectrum ${\mathrm{N}}^{+}$ fragments depends (i) phases between different electronic states ${{\mathrm{N}}_{2}}^{+}$ established process and (ii) associated with vibrational...
We propose an approach to determine the residual phase distortion directly in interaction region of few-cycle laser radiation with a gaseous target. describe how spectra generated high harmonics measured as function externally introduced dispersion into driving pulse can be used decode small amounts second- and third-order spectral phase, including sign. The diagnosis is based on analysis several key features high-harmonic spectrum: depth modulation, position cutoff, symmetry spectrum...
We present a new extension of the UKRmol electron-molecule scattering code suite, which allows one to compute ab initio photoionization and photorecombination amplitudes for complex molecules, resolved both on molecular alignment (orientation) emission angle energy photoelectron. illustrate our approach using CO$_2$ as an example, analyze importance multi-channel effects by performing calculations at different, increasing levels complexity. benchmark method comparing results with...
Transition matrix elements between electronic states where one electron can be in the continuum are required for a wide range of applications molecular R-matrix method. These include photoionization, photorecombination and photodetachment; electron-molecule scattering photon-induced processes presence an external D.C. field, time-dependent approaches to study effect exposure molecules strong laser fields. We present new algorithm, implemented as module (CDENPROP) UKRmol code suite.
Summary form only given. The advent of new XUV light sources such as free electron lasers, and the development high harmonic emission both a source direct probe, coupled with advances in detector technology laser alignment molecules, has opened up possibility observation, initiation control fastest molecular processes. Exposing aligned molecules to these short, femtosecond sub-femtosecond pulses leads ionisation, angular distribution ejected electrons encodes information about parent...
Get PDF Email Share with Facebook Tweet This Post on reddit LinkedIn Add to CiteULike Mendeley BibSonomy Citation Copy Text D. S. Brambila, A. Harvey, and O. Smirnova, "Laser-coupled R-matrix calculations for high-harmonic spectroscopy," in 19th International Conference Ultrafast Phenomena, OSA Technical Digest (online) (Optical Society of America, 2014), paper 08.Tue.P2.8. Export BibTex Endnote (RIS) HTML Plain alert Save article
We report on recent developments of the UKRmol suite, an implementation molecular R- matrix method and present examples calculations (e.g. electron scattering, photoionization, high harmonic generation, etc.) it has enabled.
We present R-matrix calculations of photoionization from NO2, resolved in energy, angle, and both neutral ionic state, for a range molecular geometries, including the vicinity 2A1/2B2 conical intersection.
By employing a nonlinear quantum kicked rotor model, we investigate the transport of energy in multidimensional chaos. Parallel numerical simulations and analytic theory demonstrate that interplay between nonlinearity Anderson localization establishes perfectly classical correspondence system, neglecting any time reversal. The resulting dynamics exhibits nonlinearly-induced, enhanced through soliton wave particles.
We have theoretically studied Anderson localization in a 2D+1 nonlinear kicked rotor model. The system shows very rich dynamical behavior, where the is suppressed and soliton wave-particles undergo superdiffusive motion.
We first briefly report on the status and recent achievements of ELPA-AEO (Eigenvalue Solvers for Petaflop Applications - Algorithmic Extensions Optimizations) ESSEX II (Equipping Sparse Exascale) projects. In both collaboratory efforts, scientists from application areas, mathematicians, computer work together to develop make available efficient highly parallel methods solution eigenvalue problems. Then we focus a topic addressed in projects, use mixed precision computations enhance...