Laser filamentation is understood to be self-channeling of intense ultrashort laser pulses achieved when the self-focusing because of the Kerr nonlinearity is balanced by ionization-induced defocusing. Here, we show that, right behind the ionized region of a laser filament, ultrashort laser pulses can couple into a much longer light channel, where a stable self-guiding spatial mode is sustained...

Imaging the structure of molecules in transient-excited states remains a challenge due to the extreme requirements for spatial and temporal resolution. Ultrafast electron diffraction from aligned molecules provides atomic resolution and allows for the retrieval of structural information without the need to rely on theoretical models. Here we use ultrafast electron diffraction from aligned molec...

We have analysed angular distributions of the photoelectron yields arising from strong-field ionization of diatomic and polyatomic linear molecules using a leading-order intense-field S-matrix theory. For molecules with active π electrons the distribution is found to strongly depend on the degree of molecular alignment, showing a nodal minimum along the laser polarization direction as a charact...

In our group, we perform successfully MALDI by using femtosecond laser techniques in order to examine the ionization process. One recent result is MALDI with ultrashort laser pulses in the near IR (central wavelength of =800 nm) [2]. In this wavelength regime, used matrix substances have no absorption bands. Experiments with different laser pulse durations suggest that multi photon ionization i...

Submitted for the DAMOP13 Meeting of The American Physical Society Mechanism of delayed double ionization in a strong laser field TURGAY UZER, Georgia Institute of Technology, FRANCOIS MAUGER, Universite de Sherbrooke, ADAM KAMOR, Georgia Institute of Technology, CRISTEL CHANDRE, Centre de Physique Theorique — Nonsequential Double Ionization (NSDI), for linearly polarized strong laser fields, h...

Analysis of multiphoton ionization of metal atoms in the saturation regime using subpicosecond KrF laser pulses" (1998). C. Singly and multiply charged ion yield curves are reported for resonant and nonresonant two-photon-ionization processes for a collection of 31 metal atoms. The atoms are created by sputtering from a solid target using an Ar-ion gun. Single and multiple ionization of these a...

BACKGROUND Matrix-assisted laser desorption/ionization (MALDI) is a soft ionization mass spectrometric technique, allowing the analysis of bio-molecules and other macromolecules. The matrix molecules require certain characteristic features to serve in the laser desorption/ionization mechanism. Therefore, only a limited number of compounds have been identified as ultraviolet- laser desorption/io...

This work presents density, spectroscopic temperature, and shockwave measurements of laser induced breakdown plasma in atmospheric air by subthreshold intensity 5.5 109 W /cm2 193 nm laser radiation. Using molecular spectroscopy and two-wavelength interferometry, it is shown that substantial ionization 1016 cm−3 occurs that is not predicted by collisional cascade CC breakdown theory. While the ...