Electron energy spectrum produced by stochastic acceleration in the laser–plasma interaction

Khalilzadeh, Elnaz; Chakhmachi, Amir; Yazdanpanah, J.

doi:10.1017/s0263034617000143

Cited by 3 publications

(6 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The amplitude of the space charge wave, wake wave, grows up to the fluid wave breaking threshold level at the end of the laser pulse wave packet over the time. 15,21 These effects observed in the phase space pattern, are associated with the generation of the high accelerated electrons and chaotic patterns in the electromagnetic approach. Another electromagnetic phenomenon which could happen in the body of the laser pulse is generation of the electrons with stochastic motion in the presence of two contra-propagate electromagnetic waves.…”

Section: Simulation Results and Discussionmentioning

confidence: 99%

“…In this context, a vast number of wave-particle phenomena become particularly interesting when the high power laser causes the electron quiver velocity to become highly relativistic. Among these phenomena, the wake field's generation, [1][2][3][4][5][6] scattering and modulation of the laser pulse, [7][8][9][10] stochastic motion of the electrons [11][12][13][14][15] and wave breaking processes [16][17][18][19] have attracted growing interest due to their vital role in the concept of laser-plasma accelerator. The last case, the wave breaking effect, is one of the most fundamental phenomena in the laser-plasma concept and it is the basis of some chaotic motion of electrons and also acceleration mechanisms such as acceleration initiated by the fluid wave breaking, direct laser acceleration, and acceleration originated from the nonlinear wave breaking via the plasma-vacuum boundary effect.…”

Section: Introductionmentioning

confidence: 99%

“…The last case, the wave breaking effect, is one of the most fundamental phenomena in the laser-plasma concept and it is the basis of some chaotic motion of electrons and also acceleration mechanisms such as acceleration initiated by the fluid wave breaking, direct laser acceleration, and acceleration originated from the nonlinear wave breaking via the plasma-vacuum boundary effect. 14,15,20 Dawson has investigated the longitudinal wave breaking in the cold plasma in one dimensional case for the first time. 21 As mentioned in the Dawson' theory, for both relativistic and nonrelativistic plasmas, when the peak of the fluid velocity of the oscillating electrons is equal to the phase velocity of the plasma wave, the longitudinal wave breaking is occurred in the cold plasma.…”

Section: Introductionmentioning

confidence: 99%

“…20 The simulation study of the influence of the nonlinear wave breaking in vacuum plasma boundary on the electron acceleration mechanism in the stochastic manner and energy distribution function of the accelerated electrons has been reported in our previous works. 14,15 Because of the non-adiabatic nature of the nonlinear wave breaking at the vacuum plasma boundary, the electrostatic characters of this phenomenon cannot be considered in terms of the quasi-static approximation. Therefore, the origin of the nonlinear wave breaking is neglected in the previous literature.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Numerical study of the wave-break in the vacuum-plasma interface during the interaction of an intense laser pulse

et al. 2017

View full text Add to dashboard Cite

In this paper, the wave break in the plasma-vacuum interface during the intense laser interaction is investigated. Since the nonlinear wave breaking is a non-adiabatic process, the fully kinetic 1D-3V Particle-In-Cell (PIC) simulation experiments are performed to identify whether that the origin of this mechanism is electromagnetic or electrostatic. Our simulation results show that the nonlinear wave breaking on the vacuum-plasma interface has electrostatic origin. In addition, it is found that for pulse lengths exceeding the plasma wavelength this electrostatic phenomenon comes in conjunction with some active electromagnetic effects having the same impact on the electron acceleration. In these regards, we conduct sophisticated simulations isolating these electromagnetic effects and study the effects of the pulse parameters such as the pulse rise time, pulse length, and pulse shape on the boundary nonlinear wave breaking. The study of the pulse rise-time variation effects shows that as the rise time of the laser pulse decreases, the number of the electrons involved in the nonlinear wave breaking, maximum energy of the trapped electrons and the path length of the accelerated electrons in the phase space are increased. Also, the study of phase space and field patterns in our simulation indicates that the reduction of the pulse flat top duration time causes that the smaller part of the electrons and the smaller portion of the wake wave involve in the nonlinear wave breaking.

show abstract

Section: Simulation Results and Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Numerical study of the wave-break in the vacuum-plasma interface during the interaction of an intense laser pulse

et al. 2017

View full text Add to dashboard Cite

show abstract

“…An investigation of stochastic acceleration resulting from nonlinear wave breaking at the vacuum-plasma interface has been published by the authors of [21]. In their newest research [22], they considered the progression of chaotic motion in plasma and mentioned that chaotic motion could emerge from the plasma density inhomogeneity at the vacuum-plasma interface.…”

Section: Numerical Investigation Of Plasma Heating During the Entranc...mentioning

confidence: 99%

Numerical investigation of plasma heating during the entrance of an intense short laser pulse into a density profile

Ghasemi¹,

Pishdast²,

Yazdanpanah³

2019

Laser Phys.

View full text Add to dashboard Cite

In this paper, plasma heating is numerically investigated using a 1D-3V particle-in-cell simulation code through the interaction between an intense short laser pulse with temporal duration, τ L = 60 fs, and a plasma having a slightly overcritical bulk density and an exponential pre-plasma density profile. The aim is to identify, via suitable parametric analysis, the most relevant nonlinear mechanisms as a function of the system parameters. As key points of our research, simulation results revealed that, for pulse-lengths less than the local nonlinear plasma wavelength, L p λ nl p , mechanisms such as vacuum-plasma interface wave-break and longitudinal plasma oscillations are the dominant mechanisms for the initiation of electron acceleration and plasma heating at earlier times. Further, for variable density scale lengths our results have proven that the heating mechanisms mentioned above can be ignored for the laser intensities less than a specific threshold value, a 0 < 3, even for short density scale length, L p = 3 µm. Meanwhile, by increasing the laser intensity to higher values, it is observed that the trend of the time history curve for the mean temperature changed in a way that the total level of temperature increased. Also, by lengthening the scale length, at first the amounts of the mean temperature curve increased, and then smoothly decreased.

show abstract

Electron energy spectrum in the field‐ionized plasma

Khalilzadeh

Chakhmachi

Dehghani

et al. 2021

Contributions to Plasma Physics

Self Cite

View full text Add to dashboard Cite

In this article, the effect of ionization on the energy spectrum of electrons within the interaction of a laser pulse with hydrogen atoms is investigated using particle-in-cell simulation codes. The results show that the behaviour of electrons' energy distribution function in the field-ionized plasma, which occurred due to the field ionization, compared with that in the pre-plasma strongly depends on the pulse shape. For short rise-time pulses (here 30 fs), due to the rapid enhancement of laser electric field, ionization occurs quickly, and as a result, there is not much difference in the electron energy in both the media.However, for pulses with rise time of 40 fs, in the pre-plasma state, the electron population reaches higher energies compared with the field-ionized plasma state. The main reason for this difference is the nonlinear wave breaking that happens earlier due to density inhomogeneity in the field-ionized plasma. On the other hand, at longer rise-time pulses (here 60 and 70 fs), electrons achieve higher energies in the field-ionized plasma than those in the case of pre-plasma.In this case, because of density fluctuations in the field-ionized plasma, the Raman backscattered radiations are seeded by a strong initial noise at the earlier times and the Mendonca condition for chaos threshold is met sooner. Therefore, the electrons gain more energy through the stochastic mechanism that is in agreement with chaotic nature of the motion.

show abstract

Electron energy spectrum produced by stochastic acceleration in the laser–plasma interaction

Cited by 3 publications

References 28 publications

Numerical study of the wave-break in the vacuum-plasma interface during the interaction of an intense laser pulse

Numerical study of the wave-break in the vacuum-plasma interface during the interaction of an intense laser pulse

Numerical investigation of plasma heating during the entrance of an intense short laser pulse into a density profile

Electron energy spectrum in the field‐ionized plasma

Contact Info

Product

Resources

About