A5052091783- Spectroscopy Techniques in Biomedical and Chemical Research
- Laser-Matter Interactions and Applications
- Diamond and Carbon-based Materials Research
- Spectroscopy and Quantum Chemical Studies
- Advanced Chemical Physics Studies
- Spectroscopy and Laser Applications
- Sparse and Compressive Sensing Techniques
- Random lasers and scattering media
- Atomic and Molecular Physics
- Fullerene Chemistry and Applications
- Spectroscopy and Chemometric Analyses
- Molecular Junctions and Nanostructures
- Photoacoustic and Ultrasonic Imaging
- Laser-induced spectroscopy and plasma
- Laser-Plasma Interactions and Diagnostics
- Electrochemical Analysis and Applications
- Optical Imaging and Spectroscopy Techniques
- Laser-Ablation Synthesis of Nanoparticles
Uppsala University
2014-2017
Swedish Defence Research Agency
2015-2016
University of Freiburg
2009-2011
University of Gothenburg
2008
In this paper, we present the HELIOS (High Energy Laser Induced Overtone Source) laboratory, an in-house high-order harmonic generation facility which generates extreme ultraviolet (XUV) photon pulses in range of 15-70 eV with monochromatized XUV pulse lengths below 35 fs. is a source for time-resolved pump-probe/two-color spectroscopy sub-50 fs range, can be operated at 5 kHz or 10 kHz. An optical parametric amplifier available pump-probe experiments wavelengths ranging from 240 nm to...
In this paper, we present a spectrometer that is designed for element-specific and time-resolved transverse magneto-optic Kerr effect experiments at the high-harmonic generation pump-probe facility High Energy Laser Induced Overtone Source (HELIOS) laboratory. HELIOS delivers photons with energies between 30 eV 72 an overall time resolution of less than 40 fs. The based on Rowland-circle geometry allows simultaneous measurements all magnetic transition-metal elements. setup also features...
This work describes construction of a source and optimisation its parameters for production cluster ion beams using material ablation by the second harmonic Nd:YAG laser (532 nm). The influence different such as carrier gas pressure, power, delay time between gas, pulses well nozzle configuration on formation are studied. For current experiments was optimized Con+ ions. Clusters with n up to 150 atoms registered time-of-flight mass spectrometer. Deposition size-selected Co50+ clusters...
We study how the ultrafast intermolecular hopping of electrons excited from water O1s core level into unoccupied orbitals depends on local molecular environment in liquid water. Our probe is resonant Auger decay hole (lifetime ∼3.6 fs), by which we show that electron-hopping rate can be significantly reduced when a first-shell molecule replaced an atomic ion. Decays resulting excitations at post-edge feature (∼540 eV) 6 m LiBr and 3 MgBr2 aqueous solutions reveal times ∼1.5 1.9 fs,...
Imaging Raman spectroscopy based on tunable filters is an established technique for detecting single explosives particles at stand-off distances. However, large light losses are inherent in the design due to sequential imaging different wavelengths, leading effective transmission often well below 1 %. The use of digital micromirror devices (DMD) and compressive sensing (CS) trace detection can improve throughput add significant flexibility compared existing systems. DMDs mature...
We present preliminary results on the performance of a basic stand-off Raman spectroscopy setup using coded apertures compared to round-to-slit fiber for light collection. Measurements were performed single 5 ns laser shots at 355 nm with target distance 5.4 meters ammonium nitrate powder. The show an increase in signal-to-noise ratio 3-8 times when aperture multiplexing setup.
We present initial results on the performance of a compressive sensing setup for Raman imaging spectroscopy standoff trace explosives detection. Hyperspectral image reconstruction is demonstrated under low signal conditions and successful spatial separation substances with close lying peaks shown.