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We consider a recently derived kinetic model for weakly relativistic quantum plasmas. We find that that the effects of spin-orbit interaction and Thomas precession may alter the linear dispersion relation for a magnetized plasma in case of…

Plasma Physics · Physics 2015-06-11 Martin Stefan , Gert Brodin

Following excitation by a strong ultra-short laser pulse, molecules develop coordinated rotational motion, exhibiting transient alignment along the direction of the laser electric field, followed by periodic full and fractional revivals…

Quantum Physics · Physics 2007-05-23 Sharly Fleischer , Ilya. Sh. Averbukh , Yehiam Prior

Nonlinear evolutions of an ultra-intense, short laser pulse due to the wake excitation inside the plasma are studied by means of detailed Particle-In-Cell (PIC) simulations and comprehensive analyses. Pulse lengths both longer and shorter…

Plasma Physics · Physics 2018-04-26 Jam Yazdanpanah , Elnaz Yazdani , Elnaz Khalilzadeh , Amir Chakhmachi

The interaction between a large number of laser filaments brought together using weak external focusing leads to the emergence of few filamentary structures reminiscent of standard filaments, but carrying a higher intensity. The resulting…

The interaction of strong laser fields with matter intrinsically provides powerful tools to image transient dynamics with an extremely high spatiotemporal resolution. Here, we study strong-field ionisation of laser-aligned molecules and…

The propagation of intense picosecond laser pulses in air in the presence of strong nonlinear self-action effects and air ionization is investigated experimentally and numerically. The model used for numerical analysis is based on the…

Plasma Physics · Physics 2016-09-13 Andreas Schmitt-Sody , Heiko G. Kurz , L. Bergé , S. Skupin , Pavel Polynkin

A model based on the strong-field and Born-Oppenheimer approximations qualitatively describes the distribution over vibrational states formed in a diatomic molecular ion following ionization of the neutral molecule by intense laser pulses.…

Atomic Physics · Physics 2007-05-23 Thomas Kim Kjeldsen , Lars Bojer Madsen

High-power femtosecond laser radiation propagates nonlinearly in air exhibiting pulse self-focusing and strong multiphoton medium ionization, which leads to the spatial fragmentation of laser pulse into highly-localized light channels…

We show that weakly-bound molecules can be probed by "shaking" in a pulsed nonresonant laser field. The field introduces a centrifugal term which expels the highest vibrational level from the potential that binds it. Our numerical…

Atomic Physics · Physics 2009-08-03 Mikhail Lemeshko , Bretislav Friedrich

We study the behavior of reduced models for the propagation of intense laser pulses in atomic gases. The models we consider incorporate ionization, blueshifting, and other nonlinear propagation effects in an ab initio manner, by explicitly…

Atomic Physics · Physics 2021-01-18 S. A. Berman , C. Chandre , J. Dubois , M. Perin , T. Uzer

We show that the decays with pressure of the alignment echoes induced in N2O-He gas mixtures by two laser pulses with various delays bring detailed information on collision-induced changes of the rotational speed. Measurements and…

The impulsive limit (the "sudden approximation") has been widely employed to describe the interaction between molecules and short, far-off-resonant laser pulses. This approximation assumes that the timescale of the laser--molecule…

Chemical Physics · Physics 2023-08-14 Volker Karle , Mikhail Lemeshko

The alternative to dynamic alignment explanation of experimental results on spatial-asymmetric dissociation of molecules in a laser field is proposed. The concept of geometrical alignment is sufficient for explanation of these results. In…

Optics · Physics 2007-05-23 V. A. Kuz'menko

A moderately intense $450$ fs laser pulse is used to create rotational wave packets in gas phase $\rm{I_2}$ molecules. The ensuing time-dependent alignment, measured by Coulomb explosion imaging with a delayed probe pulse, exhibits the…

We investigate the interplay of diffraction and nonlinear effects during propagation of very short light pulses. Adapting the factorization approach to the problem at hand by keeping the transverse-derivative terms apart from the residual…

Optics · Physics 2016-02-17 C. L. Korpa , Gy. Toth , J. Hebling

An ultrarelativistic electron beam passing through an intense laser pulse emits radiation around its direction of propagation into a characteristic angular profile. Here we show that measurement of the variances of this profile in the…

Plasma Physics · Physics 2020-07-01 T. G. Blackburn , E. Gerstmayr , S. P. D. Mangles , M. Marklund

We report experiments on field-free molecular alignment performed at FLASH, the free electron laser (FEL) in Hamburg. The impulsive alignment induced by a 100 fs near-infrared laser pulse in a rotationally cold CO_2 sample is characterized…

We investigate two types of nonlinear interaction between collinear femtosecond laser pulses with power slightly above the critical for self-focusing $P_{cr}$. In the first case we study energy exchange between filaments. The model…

Optics · Physics 2015-04-14 L. M. Kovachev , D. A. Georgieva

We develop a general method allowing one to construct the consistent theory of light pulse propagation through an atomic medium in arbitrary nonlinear regime with respect to the field strength, taking into account the light polarization,…

Optics · Physics 2015-06-16 V. I. Yudin , M. Yu. Basalaev , D. V. Brazhnikov , A. V. Taichenachev

We investigate the reversibility of laser filamentation, a self-sustained, non-linear propagation regime including dissipation and time-retarded effects. We show that even losses related to ionization marginally affect the possibility of…

Optics · Physics 2014-09-04 Nicolas Berti , Wahb Ettoumi , Jérôme Kasparian , Jean-Pierre Wolf