Energetic electron-bunch generation in a phase-locked longitudinal laser electric field

Abstract

Energetic electron acceleration processes in a plasma hollow tube irradiated by an ultraintense laser pulse are investigated. It is found that the longitudinal component of the laser field is much enhanced when a linear polarized Gaussian laser pulse propagates through the plasma tube. This longitudinal field is of π/2 phase shift relative to the transverse electric field and has a π phase interval between its upper and lower parts. The electrons in the plasma tube are first pulled out by the transverse electric field and then trapped by the longitudinal electric field. The trapped electrons can further be accelerated to higher energy in the presence of the longitudinal electric field. This acceleration mechanism is clearly illustrated by both particle-in-cell simulations and single particle modelings.

Effects of simulation dimensionality on laser-driven electron acceleration and photon emission in hollow micro-channel targets

“…Previous studies 10,34,36 have shown that, in a hollow channel without significant ion expansion, the dominant contributor to electron acceleration is the electric field in the direction of the laser propagation, i.e. the longitudinal field E x .…”

“…The interaction of high-power ultra-intense lasers and structured (both nanostructured [1][2][3][4][5][6][7] and microstructured [8][9][10][11][12][13][14][15][16][17][18] ) targets has been a topic of great interest for its capability of enhancing the laser energy conversion efficiency 1 , high-order harmonics generation 19,20 , charged particles (relativistic electrons and ions 3,4,18 ) acceleration and the production of X-ray 1,[21][22][23] to γ-ray 15,16,24 radiation. The produced charged particle and photon beams have a wide range of applications from medical ion therapy 25,26 , nuclear physics 27,28 to photon-photon pair production [29][30][31] .…”

“…The produced charged particle and photon beams have a wide range of applications from medical ion therapy 25,26 , nuclear physics 27,28 to photon-photon pair production [29][30][31] . The microstructured targets with characteristic size of surface modulation comparable to laser wavelength are able to extensively absorb laser energy through various processes, including surface plasmon resonance excitation 32 , multipass stochastic heating 33 in dense clusters, prolonged acceleration distance in hollow channels 10 and microwires 11 and relativistic transparency in prefilled channels 15 . In this paper, we examine the regime involving hollow micro-channels (see Fig.…”

“…To carry out such numerical studies, one can choose between 2D3V and 3D3V Particle-In-Cell (PIC) simulations. Both 2D [8][9][10]35,36 and 3D 13,14,17,37,38 numerical simulations have been widely used to characterize laser interactions with structured targets. The appeal of 2D simulations is that they require significantly less computational resources than 3D simulations, so one is able to perform extensive parameter scans using 2D simulations.…”

Multimillijoule terahertz radiation from laser interactions with microplasma waveguides

“…Among these structured targets is the microplasma waveguide (MPW); not only does it suppress the transverse diffraction of the pump laser, but it also enhances the longitudinal acceleration field [21,22]. Such targets have already shown their potential in electron acceleration [23,24], x-ray generation [25,26], production of ion beams [27,28] and manipulation of relativistic laser pulses [29]. In our previous work, simulations show that high charge (∼10 nC), high energy (∼100 MeV) and well-collimated (10 • ) electron bunches can be produced and accelerated by the transverse magnetic modes [30].…”