Developments in laser wakefield accelerators: From single-stage to two-stage

Abstract

Laser wakefield accelerators (LWFAs) are compact accelerators which can produce femtosecond high-energy electron beams on a much smaller scale than the conventional radiofrequency accelerators. It is attributed to their high acceleration gradient which is about 3 orders of magnitude larger than the traditional ones. The past decade has witnessed the major breakthroughs and progress in developing the laser wakfield accelerators. To achieve the LWFAs suitable for applications, more and more attention has been paid to optimize the LWFAs for high-quality electron beams. A single-staged LWFA does not favor generating controllable electron beams beyond 1 GeV since electron injection and acceleration are coupled and cannot be independently controlled. Staged LWFAs provide a promising route to overcome this disadvantage by decoupling injection from acceleration and thus the electron-beam quality as well as the stability can be greatly improved. This paper provides an overview of the physical conceptions of the LWFA, as well as the major breakthroughs and progress in developing LWFAs from single-stage to two-stage LWFAs.

Multi-GeV cascaded laser wakefield acceleration in a hybrid capillary discharge waveguide

“…Laser wakefield accelerators (LWFAs) provide a large acceleration gradient on the order of tens to hundreds of GV m −1 [1][2][3], making them attractive acceleration schemes for producing 10 GeV or even 100 GeV-scale electron beams on a compact scale [4][5][6]. Over the past decades, great progress has been made in LWFAs [7][8][9][10], yielding high-energy electron beams (e beams) with multi-GeV [11][12][13][14][15] and high-quality e beams [16][17][18][19][20][21][22] with monoenergetic, high-brightness, and low-emittance, leading to a variety of applications in coherent x-ray sources, gamma-ray sources and free electron lasers [23][24][25][26][27][28].…”

Matching-based two-color X-ray free-electron laser generation utilizing laser–plasma accelerated electron beam

“…Compact FELs driven by laser plasma accelerators (LPAs) have considerable potential to become a table-top light source with smaller scale [11][12][13][14]. The LPA generates an electron beam with energy of a few GeV within a centimetre scale of the accelerating distance [15][16][17][18][19][20][21][22]. Typical properties of the LPA beam are a peak current of up to tens of kA, a pulse duration of several femtoseconds and a normalized transverse emittance below 1 mm•mrad [20].…”

Compact beam transport system for free-electron lasers driven by a laser plasma accelerator

“…With these features, some great efforts have been made by several teams to pave the road to the LPA-driven FEL facilities [19][20][21]. For instance, the researchers in Shanghai Institute of Optics and Fine Mechanics (SIOM) have successfully developed a cascaded LPA, obtained quasimonoenergetic electron beams with the energy up to 1.3 GeV [21][22][23], and been working on FEL realization [24].…”