A5077876024- Laser-Matter Interactions and Applications
- Mass Spectrometry Techniques and Applications
- Laser-induced spectroscopy and plasma
- Atomic and Molecular Physics
- Advanced Chemical Physics Studies
- Laser Material Processing Techniques
- Advanced Fiber Laser Technologies
- Surface Modification and Superhydrophobicity
- Spectroscopy and Quantum Chemical Studies
- Laser Design and Applications
- Laser-Ablation Synthesis of Nanoparticles
- Laser-Plasma Interactions and Diagnostics
- Ion-surface interactions and analysis
- Diamond and Carbon-based Materials Research
- Nonlinear Optical Materials Studies
- Photochemistry and Electron Transfer Studies
- Chalcogenide Semiconductor Thin Films
- X-ray Spectroscopy and Fluorescence Analysis
- Electrocatalysts for Energy Conversion
- Electrohydrodynamics and Fluid Dynamics
- Quantum optics and atomic interactions
- Spectroscopy and Laser Applications
- Adhesion, Friction, and Surface Interactions
- Silicon Nanostructures and Photoluminescence
- Catalysis and Oxidation Reactions
American University of Sharjah
2016-2025
University of Sharjah
2025
Max Planck Institute of Quantum Optics
2012-2018
Griffith University
2018
Quantum (Australia)
2018
National Research Council Canada
2018
Max Planck Institute for Nuclear Physics
2018
Ludwig-Maximilians-Universität München
2017
Max Planck Computing and Data Facility
2016
King Saud University
2012-2015
We demonstrate that the structure of outermost orbitals oxygen and nitrogen can be observed in angular distribution coincident ion pairs generated by double ionization these molecules 8 fs laser pulses. do this establishing ions emerge from well defined excited electronic states O2+2 N2+2 respectively they are produced dominantly through a process which involves electron rescattering. The distributions two targets very different, reflecting different structures molecules.
We have measured coincident ion pairs produced in the Coulomb explosion of H2 by 8-30 fs laser pulses at different intensities. show how can be experimentally controlled tuning appropriate pulse duration and intensity. For less than 15 fs, we found that rescattering-induced is dominated first-return recollisions, while for longer proper intensity, third return made to major one. Additionally, choosing suitable proceeding through three distinct processes are simultaneously observable, each...
We exploit a method to precisely calibrate the peak intensity of intense laser pulses by measuring momentum transferred ion in single ionization circularly polarized light. Using this approach, we show how experimental data can be used get information about absolute rate at specific local laser-peak within focal volume. The results are compared other obtained with different methods laser-peak-intensity calibration described literature.
Proton migration is a ubiquitous process in chemical reactions related to biology, combustion, and catalysis. Thus, the ability control movement of nuclei with tailored light, within hydrocarbon molecule holds promise for far-reaching applications. Here, we demonstrate steering hydrogen simple hydrocarbons, namely acetylene allene, using waveform-controlled, few-cycle laser pulses. The rearrangement dynamics are monitored coincident 3D momentum imaging spectroscopy, described...
We studied the nuclear dynamics in diatomic molecules (N${}_{2}$, ${\mathrm{O}}_{2}$, and CO) following their interaction with intense near-IR few-cycle laser pulses. Using Coulomb-explosion imaging combination pump-probe approach, we mapped dissociation pathways of those molecular ions. identified all symmetric asymmetric breakup channels for ions up to ${\mathrm{N}}_{2}^{5+}$, ${\mathrm{O}}_{2}^{4+}$, CO${}^{4+}$. For each measured kinetic energy release (KER) spectra as a function delay...
We have measured momentum spectra and branching ratios of charged ionic fragments emitted in the double ionization ${\mathrm{D}}_{2}$ (and ${\mathrm{H}}_{2}$) molecules by short intense laser pulses. find high-energy coincident ${\mathrm{D}}^{+}$ ${\mathrm{H}}^{+}$) ion pairs with kinetic energy releases between 8 19 eV which appear for linearly polarized light but are absent circularly light. The dependence on polarization, distributions ions, intensity yield lead us to interpret these as...
We have measured angular distributions of ion fragments produced in dissociative double ionization CO, $\mathrm{C}{\mathrm{O}}_{2}$, and ${\mathrm{C}}_{2}{\mathrm{H}}_{2}$ by intense ultrashort laser pulses. This report extends similar recent studies ${\mathrm{O}}_{2}$ ${\mathrm{N}}_{2}$ to a wider set molecules. found that for sub-$10\text{\ensuremath{-}}\mathrm{fs}$ pulses sufficiently low intensity the fragments' all studied molecules are determined dependence first step. Those...
We have measured momentum-space images of low-energy electrons generated by the interaction short intense laser pulses with argon atoms at high intensities. done this over a wavelength range from 400 to 800 nm. The spectra show considerable structure in both energy and angular distributions electrons. Some, but not all, features can be identified as multi-photon resonances. shows regularity which transcends resonant may due instead diffraction. complexity results defies easy model-dependent...
Femtosecond (FS) laser-induced surface structuring is a robust, maskless, non-contact, and single-step process for producing micro- nanoscale structures on material’s surface, which remarkably alters the optical, chemical, wetting, tribological properties of that material. Wettability control, in particular, high significance various applications, including self-cleaning, anti-fouling, anti-icing, anti-corrosion, and, recently, oil–water separation. Due to growing energy demands rapid...
The ever-growing interest in additive manufacturing (AM) is evidenced by its extensive utilisation to manufacture a broad spectrum of products across range industries such as defence, medical, aerospace, automotive, and electronics. Today, most laser-based AM carried out employing continuous-wave (CW) long-pulsed lasers. CW lasers have the downside that thermal energy imparted laser diffuses around irradiated spot often leads creation heat-affected zones (HAZs). Heat-affected may degrade...
We report a robust two-step method for developing adherent and anticorrosive molybdenum (Mo)-based coatings over an aluminum (Al) 6061 alloy substrate using femtosecond (fs) laser. The fs laser nanostructuring of Al in air gives rise to regular arrays microgrooves exhibiting superhydrophilic surface properties. microstructured is further coated with Mo layer the fs-pulsed deposition (fs-PLD) technique. combination two treatments (microstructuring followed by coating) enabled development...
We have used intense few-cycle laser pulses in a pump-probe arrangement to directly map, with high time resolution, the simultaneous evolution on two different potential curves of wave packets created when ${\mathrm{H}}_{2}$ $({\mathrm{D}}_{2})$ molecules were ionized by strong field. The experimental ``snapshots'' obtained measuring coincidence kinetic energy distribution proton (deuteron) pairs produced Coulomb explosion $\mathrm{H}_{2}{}^{+}$ $(\mathrm{D}_{2}{}^{+})$ molecular ions as...
We have used momentum imaging techniques to measure in high resolution the kinetic energy release spectra and angular distributions of coincident O+ N+ ion pairs produced by short laser pulses (8–35 fs) on targets N2 O2 at peak intensities between 1 12 × 1014 W cm−2. record full vectors both members each pair achieve a less than 0.3 eV. find that process proceeds through well-defined electronic states excited molecular dications. Using linear circularly polarized light, we identify two...
We studied the angular distributions of fragmented ions diatomic molecules in an intense linearly polarized short laser pulse. In addition to well-known dynamic alignment neutral before ionization, we identified a more important post ionization effect molecular ions. The latter is modelled quantum mechanically as resulting from breakup rotating linear rotor. showed that only for very pulses are two mechanisms not important. this case mimic shape electronic density outermost orbital.
In this work, the corrosion resistance of mild steel surface nanostructured with a femtosecond laser and coated high resistant CrCoNi (CCN) medium entropy alloy through magnetron sputtering is studied. Substantial improvement in protection was achieved by applying combination high-power nano-structuring at ambient conditions thin-film coating alloy. XRD analysis revealed that structuring increases susceptibility surfaces to Fe2O3 nucleation oxidation. The wettability measurements...
One of the important aspects manipulating and controlling liquid transport is design membrane surfaces. Janus membranes with opposite wettability characteristics can be manufactured for efficient directional water transfer. In this work, two types materials were used to fabricate an asymmetric behavior: copper foam mesh. side was treated by scanning a femtosecond laser beam, as result which it converted superhydrophilic state, while untreated remained hydrophobic. Both demonstrated excellent...