A5047377599- Laser-Matter Interactions and Applications
- Mass Spectrometry Techniques and Applications
- Advanced Chemical Physics Studies
- Atomic and Molecular Physics
- Laser-induced spectroscopy and plasma
- Spectroscopy and Quantum Chemical Studies
- Photosynthetic Processes and Mechanisms
- Atmospheric Ozone and Climate
- Molecular Spectroscopy and Structure
- Geological and Geochemical Analysis
- Catalysis and Oxidation Reactions
- Radioactive element chemistry and processing
- Cold Atom Physics and Bose-Einstein Condensates
- Laser Design and Applications
- Graphene research and applications
- Cytokine Signaling Pathways and Interactions
- Gas Sensing Nanomaterials and Sensors
- Quantum Mechanics and Applications
- Atomic and Subatomic Physics Research
- Catalytic Processes in Materials Science
- CAR-T cell therapy research
- Atmospheric and Environmental Gas Dynamics
- Geochemistry and Geologic Mapping
- Viral Infectious Diseases and Gene Expression in Insects
- Photoreceptor and optogenetics research
TU Wien
2014-2022
Jackson Laboratory
2022
Wuhan Institute of Physics and Mathematics
2020
Chinese Academy of Sciences
2020
University of Basel
2013-2016
We investigate the possibility of using molecular alignment for controlling relative probability individual reaction pathways in polyatomic molecules initiated by electronic processes on few-femtosecond time scale. Using acetylene as an example, it is shown that aligning axis with respect to polarization direction ionizing laser pulse does not only allow us enhance or suppress overall fragmentation yield a certain channel but, more importantly, determine starting from same parent ion. show...
We demonstrate the detection of high-lying Rydberg states produced in strong laser fields with coincidence spectroscopy. Electron emission after interaction pulses atoms and molecules is measured together parent ions measurements. These electrons originate from quantum numbers $n\ensuremath{\sim}20$ up to $n\ensuremath{\lesssim}120$ formed by frustrated field ionization. Ionization rates are retrieved ionization signal these states. Simulations show that both tunneling a weak dc...
This works shows a new approach to study the electron recapture process during double and multiple ionization of atoms. scheme is applicable non-dissociative processes in molecules, which are not accessible with existing methods based on measurement kinetic energy released from fragmentation processes. The experiments show transition frustrated argon non-sequential scenario sequential scenario.
ABSTRACT The lack of genetically diverse preclinical animal models in basic biology and efficacy testing has been cited as a potential cause failure clinical trials. We developed characterized five RAG1 null mouse strains that allow xenografts to grow. In these strains, we the growth breast cancer, leukemia glioma cell lines. found wide range characteristics were far more dependent on strain than tumor type. For cancer line, spectrum xenograft/tumor at structural, histological, cellular...
The alignment-dependent ionization of acetylene and ethylene in short laser pulses is investigated the framework time-dependent density-functional theory coupled with Ehrenfest dynamics. molecular alignment found to have a substantial effect on total ionization. Bond stretching shown cause an increase efficiency, i.e., enhanced ionization, qualitative agreement previous theoretical investigations. It also demonstrated that mechanism greatly enhances from inner valence orbitals, orbitals...
We present the results of a combined experimental and numerical study on strong-field ionisation acetylene performed with aim identifying mechanism behind previously reported surprisingly large multi-electron probabilities polyatomic molecules. Using coincidence momentum imaging techniques time-dependent density functional simulations, we show that efficient is due to action significant geometrically induced energy upshift most relevant valence orbitals as C–H distance stretches beyond about...
We experimentally and theoretically investigated the deprotonation process on nanosecond to microsecond timescale in ethylene acetylene molecules, following their double ionization by a strong femtosecond laser field. In our experiments we utilized coincidence detection with reaction microscope technique, found that both lifetime of long-lived dication leading delayed relative channel strength compared prompt one have no evident dependence pulse duration peak intensity. Quantum chemical...
We visualize and control molecular dynamics taking place on intermediately populated states during different sequential double ionization pathways of CO2 using a sequence two delayed laser pulses which exhibit peak intensities. Measured yields CO22+ fragment pairs CO+/O+ as function delay between the are weakly modulated by various vibronic in CO2+. By Fourier analysis modulations we identify show that they can be assigned to merely pathways. demonstrate reversing it becomes possible pathway...
Oxygen ($O_2$) is one of the most important elements required to sustain life. The concentration $O_2$ on Earth has been accumulated over millions years and a direct connection with that $CO_2$. Further, $CO_2$ plays an role in many other planetary atmospheres. Therefore, molecular reactions involving are critical for studying atmospheres such planets. Existing studies dissociation exclusively focused C--O bond breakage. Here we report first experiments observation formation from strong...
We report on an experimental and theoretical study of the ionization-fragmentation dynamics argon dimers in intense few-cycle laser pulses with a tagged carrier-envelope phase. find that field-driven electron transfer process from one atom across system boundary to other triggers sub-cycle electron-electron interaction neighboring atom. This attosecond electron-transfer between distant entities its implications manifest themselves as distinct phase-shift measured asymmetry emission curves...
The paper investigates the laser-induced dissociation recombination process of carbon dioxide. coincidence measurements all involved particles show that one electron can recombine to two ionic fragments during dissociative double ionization dioxide in a strong laser field. Photoelectron momentum distributions measured experiments further reveal second ionized has much higher probability than first electron. results may trigger experimental and theoretical studies on molecular reactions.
Electronic absorption spectra of C7O, neutral and cationic, have been obtained after mass selection deposition into 6 K neon matrices. The band system with origin at 305.1 nm is identified as the (2) 1Σ+ ← X electronic transition linear absorption, onset 276.0 nm, to (4) 2Σ+ C7O+ on basis experimental observations theoretical calculations.
We show that (near-)zero energy proton emission from H$_2^+$ in strong two-color and broadband laser fields is dominated by a stimulated Raman scattering process taking place on the electronic ground state. It furthermore shown region asymmetry ejection induced asymmetric due to interplay of several processes, rather than only pathway interferences, with vibrational trapping (or bond-hardening) key role.
Received 13 February 2017DOI:https://doi.org/10.1103/PhysRevA.95.029903©2017 American Physical SocietyPhysics Subject Headings (PhySH)Research AreasAtomic & molecular processes in external fieldsMultiphoton or tunneling ionization excitationPhotodissociationAtomic, Molecular Optical
C7H4O2+ and C7H5O2+ ions the respective neutrals have been investigated by absorption spectroscopy in neon matrixes following mass selection of produced from salicylic acid. Three electronic transitions starting at 649.6, 431.0, 372.0 nm are detected for assigned on basis CASPT2 energies Franck-Condon simulations as excitations X 2A″ to 1 2A″, 2 3 states 6-(oxomethylene)-2,4-cyclohexadien-1-one ion (A+). Absorptions commencing 366.4 observed 2A' ← transition (2-hydroxyphenyl)methanone (J+)....
Abstract We report on the results of a joint experimental and numerical study sub-cycle laser field-driven electron dynamics that underlie population highly excited electronic states in multiply ionized argon dimers by recapture processes. Our experiments using few-cycle pulses with known carrier-envelope phase (CEP) combination reaction microscopy reveal distinct CEP-dependence emission process and, furthermore, small but significant CEP-offset to scenario which no are produced. With help...
Strong-field induced valence electron excitation is a common process in strong field interaction with atoms and molecules. In the case of polyatomic molecules, effects ionization from low-lying molecular orbitals nuclear dynamics during can play critical roles for excitation. this work, we investigate involved singly ionized acetylene laser using alignment dependence intensity dependence. Additionally, are identified difference kinetic energy release angular distribution laser-induced...
We observed high-lying (n>238) Rydberg states which survived from strong field interaction of atoms and molecules with electron ion coincidence detection. The are measured through ionization weak DC fields.
We report experimental observation of "slow" fragmentation from ethylene molecules on nanosecond or even microsecond timescale after their interaction with femtosecond laser pulses. Our results indicate that such process originates meta-stable high-lying vibrational states ions.
We experimentally observed high-lying (n>238) Rydberg states which are formed through recapture of electrons after strong field interaction in atoms and small molecules using electron ion coincidence detection. The identified weak DC field-induced ionization.
We show that the interplay of electron removal and nuclear dynamics on few femtosecond range, controlled by duration few-cycle laser pulses, determines ratio C2H43+ fragmentation into two respectively three moieties.
Using a double-pulse scheme we visualize and control molecular dynamics taking place on intermediate states populated during different sequential double ionization pathways of CO2. Exchanging the pulse- sequence can almost completely switch pathway.
We demonstrated coincidence detection of high-lying Rydberg states populated in strong field interaction. Simulations reveals the measured ionization signal originates from DC induced tunneling and photoionization by blackbody radiation.