arXiv subjects

E. N. Nerush

Publications and source records attributed to E. N. Nerush.

At least 19 recordsLinked to original sources

arXiv2025

QED cascade initiation via reflection of a multipetawatt laser pulse from a self-organized parabolic plasma mirror

The self-sustained or avalanche-type cascade is an intriguing prediction of strong-field quantum electrodynamics (QED) that has yet to be observed in laboratories. It is accompanied by the conversion of electromagnetic energy into gamma photons and electron-positron ($e^-e^+$) pairs, whose number increases exponentially over time. We investigate a simple configuration to initiate a QED cascades: it is based on the superposition of an incident multipetawatt laser pulse and its reflection from a solid target. The incident laser pulse < > the initially flat target surface, creating a parabolic mirror that focuses the reflected radiation. For the considered setup the threshold laser power is about $7\,\text{PW}$. With a $27\,\text{PW}$ laser pulse, positron production exhibits clear signatures of an avalanche-type cascade, including exponential growth and more than 15 positron generations with similar energy spectra. Therefore, observing an avalanche-type QED cascade does not require the use of multiple laser channels with precise spatio-temporal synchronization, as previously supposed.

physics.plasm-ph↗

arXiv2025

Collimated QED Cascades with Curved Plasma Mirror

Converting light into matter has been a longstanding goal in physics, particularly the creation of electron-positron pairs through quantum electrodynamic (QED) processes. While current approaches using multiple colliding laser pulses can achieve this conversion, they struggle to produce well-collimated particle beams - a crucial requirement for practical applications. Here we demonstrate that a single ultra-intense laser pulse, when reflected from a curved plasma mirror, can generate highly collimated electron-positron pairs with unprecedented efficiency. By focusing the laser to field strengths exceeding $a_0 > 2000$, our method triggers QED cascades that produce tightly focused particle beams, distinctly different from the diffuse plasmas created by conventional multi-laser setups. The technique works even at relatively modest laser powers of 13PW, making it immediately testable at existing facilities. This breakthrough opens new possibilities for studying fundamental QED processes and generating controlled matter-antimatter plasmas.

physics.plasm-ph↗

arXiv2023

Short-term evolution of electron wave packet in a constant crossed field with radiative corrections

We study the dynamics of an electron wave packet in a strong constant crossed electromagnetic field with account for radiative corrections due to interaction of the electron with the vacuum fluctuations. We evaluate a wave packet composed of the solutions to the Dyson-Schwinger equation, which describes electron propagation without emission of real photons. Spacetime dependence of the wave packet is obtained analytically for a short time interval, the more restricted from above the wider is the packet in momentum space. The radiative corrections alter the electron wavefunction, resulting in particular in a damping of the wave packet. The expectation value of the Dirac spin operator also gets modified.

hep-th↗

arXiv2022

Opacity of relativistically underdense plasmas for extremely intense laser pulses

It is generally believed that relativistically underdense plasma is transparent for intense laser radiation. However, particle-in-cell simulations reveal abnormal laser field absorption above the intensity threshold about~$3 \times 10^{24}~\mathrm{W}\,\mathrm{cm}^{-2}$ for the wavelength of $1~μ\mathrm{m}$. Above the threshold, the further increase of the laser intensity doesn't lead to the increase of the propagation distance. The simulations take into account emission of hard photons and subsequent pair photoproduction in the laser field. These effects lead to onset of a self-sustained electromagnetic cascade and to formation of dense electron-positron ($e^+e^-$) plasma right inside the laser field. The plasma absorbs the field efficiently, that ensures the plasma opacity. The role of a weak longitudinal electron-ion electric field in the cascade growth is discussed.

physics.plasm-ph↗

arXiv2022

High-order corrections to the radiation-free dynamics of an electron in the strongly radiation-dominated regime

A system of reduced equations is proposed for the electron motion in the strongly-radiation dominated regime for an arbitrary electromagnetic field configuration. The developed approach is used to analyze various scenarios of an electron dynamics in the strongly-radiation dominated regime: motion in rotating electric and magnetic fields, longitudinal acceleration in a plane wave and in a plasma wakefield. The obtained results show that the developed approach is able to describe features of the electron dynamics, which are essential to a certain scenario, but which could not be captured in the framework of the original radiation-free approximation [A. S. Samsonov et al., Phys. Rev. A 98, 053858 (2018); A. Gonoskov and M. Marklund, Phys. Plasmas 25, 093109 (2018)]. The results are verified by numerical integration of non-reduced motion equations with account of radiation reaction in both semi-classical and fully quantum cases.

physics.plasm-ph↗

arXiv2021

Radiation reaction-dominated regime of wakefield acceleration

We study electron acceleration in a plasma wakefield under the influence of the radiation-reaction force caused by the transverse betatron oscillations of the electron in the wakefield. Both the classical and the strong quantum-electrodynamic (QED) limits of the radiation reaction are considered. For the constant accelerating force, we show that the amplitude of the oscillations of the QED parameter $χ$ in the radiation-dominated regime reaches the equilibrium value determined only by the magnitude of the accelerating field, while the averaged over betatron oscillations radiation reaction force saturates at the value smaller than the accelerating force and thus is incapable of preventing infinite acceleration. We find the parameters of the electron bunch and the plasma accelerator for which reaching such a regime is possible. We also study effects of the dephasing and the corresponding change of accelerating force over the course of acceleration and conclude that the radiation-dominated regime is realized both in cases of single-stage acceleration with slow dephasing (usually corresponding to bunch-driven plasma accelerators) and multi-stage acceleration with fast dephasing (corresponding to the use of laser-driven accelerators).

physics.plasm-ph↗

arXiv2021

Beamstrahlung-enhanced disruption in beam-beam interaction

The radiation reaction (beamstrahlung) effect on particle dynamics during interaction of oppositely charged beams is studied. It is shown that the beam focusing can be strongly enhanced due to beamstrahlung. An approximate analytical solution of the motion equation including the radiation reaction force is derived. The disruption parameter is calculated for classical and quantum regime of beamstrahlung. The analytical model is verified by QED-PIC simulations. The model for head-on collision of long beams undergoing a number of betatron oscillation during interaction is also developed. It is demonstrated that the beamstrahlung-enhanced disruption effect can play a significant role in future lepton colliders with high-current particle beams.

physics.acc-ph↗

arXiv2020

Hydrodynamical model of QED cascade expansion in an extremely strong laser pulse

Development of the self-sustained quantum-electrodynamical (QED) cascade in a single strong laser pulse is studied analytically and numerically. The hydrodynamical approach is used to construct the analytical model of the cascade evolution, which includes the key features of the cascade observed in 3D QED particle-in-cell (QED-PIC) simulations such as the magnetic field predominance in the cascade plasma and laser energy absorption. The equations of the model are derived in the closed form and are solved numerically. Direct comparison between the solutions of the model equations and 3D QED-PIC simulations shows that our model is able to describe the complex nonlinear process of the cascade development qualitatively well. The various regimes of the interaction based on the intensity of the laser pulse are revealed in both the solutions of the model equations and the results of the QED-PIC simulations.

physics.plasm-ph↗

arXiv2020

Quasiclassical approach to synergic synchrotron-Cherenkov radiation in polarized vacuum

The photon emission by an ultrarelativistic charged particle in extremely strong magnetic field is analyzed, with vacuum polarization and photon recoil taken into account. The vacuum polarization is treated phenomenologically via refractive index. The photon emission occurs in the synergic (cooperative) synchrotron-Cherenkov process [J. Schwinger, W. Tsai and T. Erber, Annals of Physics, 96 303 (1976)] which is similar to the synchrotron emission rather than to the Cherenkov one. For electrons, the effect of the vacuum polarization on the emission spectrum is not evident even beyond the probable onset of non-perturbative quantum electrodynamics (QED). However, the effect of the vacuum polarization on the emission spectrum can be observable for muons already at $γB / B_S \approx 30$, with $γ$ the muon Lorentz factor, $B$ the magnetic field strength and $B_S$ the critical QED field. Nevertheless, vacuum polarization leads to only 10% enhancement of the maximum of the radiation spectrum.

hep-ph↗

arXiv2019

Probing non-perturbative QED with electron-laser collisions

The vast majority of QED results are obtained in relatively weak fields and so in the framework of perturbation theory. However, forthcoming laser facilities providing extremely high fields can be used to enter not-yet-studied regimes. Here, a scheme is proposed that might be used to reach a supercritical regime of radiation reaction or even the fully non-perturbative regime of quantum electrodynamics. The scheme considers the collision of a 100 GeV-class electron beam with a counterpropagating ultraintense electromagnetic pulse. To reach these supercritical regimes, it is unavoidable to use a pulse with ultrashort duration. Using two-dimensional particle-in-cell simulations, it is therefore shown how one can convert a next-generation optical laser to an ultraintense ($I\approx 2.9\times 10^{24} \text{ W} \, \text{cm}^{-2}$) attosecond (duration $\approx$ 150 as) pulse. It is shown that if the perturbation theory persists in extremely fields, the spectrum of secondary particles can be found semi-analytically. In contrast, a comparison with experimental data may allow differentiating the contribution of high-order radiative corrections if the perturbation theory breaks.

physics.plasm-ph↗

arXiv2019

Laser-driven vacuum breakdown waves

It is demonstrated by three-dimensional quantum electrodynamics --- particle-in-cell (QED-PIC) simulations that vacuum breakdown wave in the form of QED cascade front can propagate in an extremely intense plane electromagnetic wave. The result disproves the statement that the self-sustained cascading is not possible in a plane wave configuration. In the simulations the cascade initiates during laser-foil interaction in the light sail regime. As a result, a constantly growing electron-positron plasma cushion is formed between the foil and laser radiation. The cushion plasma efficiently absorbs the laser energy and decouples the radiation from the moving foil thereby interrupting the ion acceleration. The models describing propagation of the cascade front and electrodynamics of the cushion plasma are presented and their predictions are in a qualitative agreement with the results of numerical simulations.

physics.plasm-ph↗

arXiv2019

Global constant field approximation for radiation reaction in collision of high-intensity laser pulse with electron beam

In the laser --- electron beam head-on interaction electron energy can decrease due to radiation reaction, i.e. emission of photons. For 10--100~fs laser pulses and for the laser field strength up to the pair photoproduction threshold, it is shown that one can calculate the resulting electron and photon spectra as if the electron beam travels through a constant magnetic field. The strength of this constant field and the interaction time are found as functions of the laser field amplitude and duration. Using of constant field approximation can make a theoretical analysis of stochasticity of the radiation reaction much simpler in comparison with the case of alternating laser field, also, it allows one to get electron and photon spectra much cheaper numerically than by particle-in-cell simulations.

physics.plasm-ph↗

arXiv2018

Asymptotic electron motion in strong radiation-dominated regime

We study electron motion in electromagnetic (EM) fields in the radiation-dominated regime. It is shown that the electron trajectories become close to some asymptotic trajectories in the strong field limit. The description of the electron dynamics by this asymptotic trajectories significantly differs from the ponderomotive description that is barely applicable in the radiation-dominated regime. The particle velocity on the asymptotic trajectory is completely determined by the local and instant EM field. The general properties of the asymptotic trajectories are discussed. In most of standing EM waves (including identical tightly-focused counter-propagating beams) the asymptotic trajectories are periodic with the period of the wave field. Furthermore, for a certain model of the laser beam we show that the asymptotic trajectories are periodic in the reference frame moving along the beam with its group velocity that may explain the effect of the radiation-reaction trapping.

physics.plasm-ph↗

arXiv2017

Weibel instability in hot plasma flows with production of gamma-rays and electron-positron pairs

We present the results of theoretical analysis and numerical simulations of the Weibel instability in two counter-streaming hot relativistic plasma flows, e.g. flows of electron-proton plasma having rest-mass density $ρ\sim 10^{-4}\; \text{g}\, \text{cm}^{-3}$, Lorentz factors $Γ\sim 10$ and proper temperature $T \sim 10^{13}\; \text{K}$. The instability growth rate and the filament size at the linear stage are found analytically, and are in qualitative agreement with results of three-dimensional particle-in-cell simulations. In the simulations, incoherent synchrotron emission and pair photoproduction in electromagnetic fields are taken into account. If the plasma flows are dense, fast and/or hot enough, the overall energy of synchrotron photons can be much larger than the energy of generated electromagnetic fields. Furthermore, a sizable number of positrons can be produced due to the pair photoproduction in the generated magnetic field. We propose a rough criterion for judging copious pair production and synchrotron losses. By means of this criterion we conclude that incoherent synchrotron emission and pair production during the Weibel instability can have implications for the collapsar model of gamma-ray bursts.

astro-ph.HE↗

arXiv2017

Near-surface electron acceleration during intense laser-solid interaction in the grazing incidence regime

When a relativistically intense p-polarized laser pulse is grazingly incident onto a planar solid-state target, a slightly superluminal field structure is formed near the target surface due to the incident and reflected waves superposition. This field structure can both extract the electrons from the target and accelerate them. It is theoretically shown that the acceleration is possible and stable for a wide range of electron initial conditions. PIC simulations confirm that this mechanism can actually take place for realistic parameters. As a result, the electron bunches with charge of tens of nC and GeV-level energy can be produced using a laser intensity $10^{21}-10^{22}$ W/cm${}^2$. It is also shown that the presence of a preplasma can increase the acceleration rate, which becomes possible because of more efficient electron injection into the accelerating field structure.

physics.plasm-ph↗

arXiv2016

Production and dynamics of positrons in ultrahigh intensity laser-foil interactions

The electron-positron pair production accompanying interaction of a circularly polarized laser pulse with a foil is studied for laser intensities higher than $10^{24}$W cm$^{-2}$. The laser energy penetrates into the foil due to the effect of the relativistic hole-boring. It is demonstrated that the electron-positron plasma is produced as a result of quantum-electrodynamical cascading in the field of the incident and reflected laser light in front of the foil. The incident and reflected laser light makes up the circularly polarized standing wave in the reference frame of the hole-boring front and the pair density peaks near the nodes and antinodes of the wave. A model based on the particle dynamics with radiation reaction effect near the magnetic nodes is developed. The model predictions are verified by 3D PIC-MC simulations.

physics.plasm-ph↗

arXiv2015

Incoherent synchrotron emission of laser-driven plasma edge

When a relativistically intense linearly polarized laser pulse is incident on an overdense plasma, a dense electron layer is formed on the plasma edge which relativistic motion results in high harmonic generation, ion acceleration and incoherent synchrotron emission of gamma-photons. Here we present a self-consistent analytical model that describes the edge motion and apply it to the problem of incoherent synchrotron emission by ultrarelativistic plasma electrons. The model takes into account both coherent radiation reaction from high harmonics and incoherent radiation reaction in the Landau-Lifshitz form. The analytical results are in agreement with 3D particle-in-cell simulations in a certain parameter region that corresponds to the relativistic electronic spring interaction regime.

physics.plasm-ph↗

arXiv2015

Optimized multibeam configuration for observation of QED cascades

QED cascades in intense electromagnetic field can occur if the dynamical quantum parameter $χ$ of a seed electron, which in Compton units coincides with the electron proper acceleration, attains the order of unity. We derive general expression for $χ$ of an initially slow electron in an arbitrary electromagnetic field for a time range $t\ll 1/ω$, where $ω$ is the field carrier frequency. Using this formula, we consider a special field configuration of multiple colliding focused laser beams and optimize it to provide cascade development at laser power below $10$ PW and intensity of the order of $10^{23}$W/cm$^2$. Such parameters of the beams will be obtained with a new generation of laser facilities, particularly the ELI Beamlines, in the coming years.

physics.plasm-ph↗