Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "self-focusing" wg kryterium: Temat


Wyświetlanie 1-6 z 6
Tytuł:
Ponderomotive self-focusing of a short laser pulse under a plasma density ramp
Autorzy:
Kant, N.
Saralch, S.
Singh, H.
Powiązania:
https://bibliotekanauki.pl/articles/146636.pdf
Data publikacji:
2011
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
self-focusing
underdense plasma
plasma density ramp
ponderomotive force
short laser pulse
Gaussian beam
Opis:
The ponderomotive self-focusing of a short laser pulse in an underdense plasma under a plasma density ramp is analyzed. The pulse may acquire a minimum spot size due to the ponderomotive self-focusing. Beyond the focus, the nonlinear refraction starts weakening, and the spot size of the laser pulse increases, resulting in an oscillatory self-focusing and defocusing behavior of the beam with the propagation distance. In order to minimize the defocusing, we introduce a localized upward plasma density ramp. Due to the upward plasma density ramp, the laser beam retains a minimum spot size. Self-focusing becomes stronger with a mild ripple as the propagation distance increases. The conditions for the ponderomotive self-focusing for suitable parameters of the laser beam and the plasma are determined. The plasma density ramp of the considered type may be observed in gas jet plasma experiments.
Źródło:
Nukleonika; 2011, 56, 2; 149-153
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Gaussian beam evolution in inhomogeneous nonlinear media with absorption
Autorzy:
Berczynski, P.
Powiązania:
https://bibliotekanauki.pl/articles/173434.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
Gaussian beam diffraction and self-focusing
complex geometrical optics
inhomogeneous and nonlinear saturable fibres
Opis:
The method of complex geometrical optics (CGO) is presented, which describes Gaussian beam (GB) diffraction and self−fo− cusing in smoothly inhomogeneous and nonlinear Kerr type and saturable fibres. CGO reduces the problem of Gaussian beam evolution in inhomogeneous and nonlinear media to the system of the first order ordinary differential equations for the complex curvature of the wave front and for GB amplitude, which can be readily solved both analytically and numerically. As a result, CGO radically simplifies the description of Gaussian beam diffraction and self−focusing effects as compared to other methods of nonlinear optics such as variational method approach, method of moments and beam propagation method. The power of CGO method is presented on the example of Gaussian beam propagation in saturable fibres with either focu− sing and defocusing refractive profiles. Besides, the influence of initial curvature of the wave front, phenomenon of weak ab− sorption and effect of either transverse and longitudinal inhomogeneity on GB propagation in nonlinear fibres is discussed in this paper.
Źródło:
Optica Applicata; 2013, 43, 3; 583-595
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Enhanced resonant second harmonic generation in plasma based on density transition
Autorzy:
Kant, N.
Thakur, V.
Powiązania:
https://bibliotekanauki.pl/articles/148562.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
second harmonic generation
laser
plasma density ramp
self-focusing
Opis:
Resonant second harmonic generation of a relativistic self-focusing laser in plasma with density ramp profile has been investigated. A high intense Gaussian laser beam generates resonant second harmonic beam in plasma with density ramp profile. The second harmonic undergoes periodic focusing in the plasma channel created by the fundamental wave. The normalized second harmonic amplitude varies periodically with distance and attains maximum value in the focal region. Enhancement in the second harmonic amplitude on account of relativistic self-focusing of laser based on plasma density transition is seen. Plasma density ramp plays an important role to make self-focusing stronger which leads to enhance the second harmonic generation in plasma.
Źródło:
Nukleonika; 2015, 60, 2; 355-360
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermal Self-Action of Acoustic Beams Containing Several Shock Fronts
Autorzy:
Perelomova, A.
Powiązania:
https://bibliotekanauki.pl/articles/177213.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
thermal self-focusing
acoustic beam
acoustic wave with discontinuity
acoustic shock waves
thermal lens
Opis:
Thermal self-action of an acoustic beam with one discontinuity or several shock fronts is studied in a Newtonian fluid. The stationary self-action of a single sawtooth wave with discontinuity (or some integer number of these waves), symmetric or asymmetric, is considered in the cases of self-focusing and self-defocusing media. The results are compared with the non-stationary thermal self-action of the periodic sound. Thermal self-action of a single shock wave which propagates with the various speeds is considered.
Źródło:
Archives of Acoustics; 2015, 40, 4; 539-546
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Non-stationary thermal self-action of acoustic beams containing fronts in thermoconducting fluid
Autorzy:
Perelomova, A.
Powiązania:
https://bibliotekanauki.pl/articles/1938590.pdf
Data publikacji:
2016
Wydawca:
Politechnika Gdańska
Tematy:
non-stationary thermal self-focusing of an acoustic beam
shock acoustic wave
thermal lens
Opis:
Non-stationary thermal self-action of a periodic or impulse acoustic beam containing shock fronts in a thermoconducting Newtonian fluid is studied. Self-focusing of a saw-tooth periodic and impulse sound is considered, as well as that of a solitary shock wave which propagates with the linear sound speed. The governing equations of the beam radius are derived. Numerical simulations reveal that the thermal conductivity weakens the thermal self-action of the acoustic beam.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2016, 20, 2; 219-230
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Self-refraction of impulse and quasi-stationary acoustic beams containing shock fronts in a Newtonian fluid
Autorzy:
Perelomova, Anna
Powiązania:
https://bibliotekanauki.pl/articles/1954614.pdf
Data publikacji:
2020
Wydawca:
Politechnika Gdańska
Tematy:
self-refraction of acoustic beam
self-focusing of sound
self-action of beams with shock fronts
samorefrakcja wiązki akustycznej
samoskupianie się dźwięku
samoczynność belek
fronty uderzeniowe
Opis:
The self-refraction of some beams in a Newtonian fluid is theoretically studied. Asingle pulse that takes the shape of an isosceles triangle at a transducer and a solitary shockwave are considered as examples. The novelty lies in the consideration of a quasi-stationaryshock wave (with positive or negative pressure) and negative triangular pulses. We concludethat waveforms with negative excess pressure undergo self-focusing, in contrast to those withpositive excess pressure. The difference in self-refraction of quasi-stationary and impulse beamsis revealed by means of numerical modeling.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2020, 24, 1; 17-28
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-6 z 6

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies