Electrons are accelerated to high energy using laser-generated plasma in laser wakefield accelerators (LWFAs). Measuring hundreds of meters versus centimeters, these devices are much smaller than radio frequency-based particle accelerators, making them more affordable and effective substitutes. The ability of LWFAs to produce particles with energies comparable to their conventional counterparts still needs to be proven by researchers. Now, Xinzhe Zhu of Shanghai Jiao Tong University and colleagues have come one step closer to this goal by demonstrating a mechanism to bind multiple LWFAs in a way that increases their acceleration potential.
In an LWFA, charged particles drive a plasma wave produced by a powerful laser up to relativistic velocities. A single LWFA can only provide a few GeV of particle energy because laser energy decreases with distance and the particle beam and plasma wave quickly lose coordination. These problems can be solved by sending the particles over several interconnected LWFAs. However, current methods for combining LWFAs require the beam to be focused at each link, reducing the efficiency of the process.
Zhu and colleagues are able to circumvent this problem by maintaining a continuous channel for particles and aiming each LWFA's laser at the medium along a curved trajectory. To demonstrate this approach, the group created a curved, 3 cm long tube inside a sapphire block. A pre-accelerated electron beam enters the LWFA along a straight "highway", while the laser travels along a curved "ramp" driven by changes in plasma density. The arrangement resembles a highway ramp.
Zhu and colleagues show how their system can both accelerate injected electrons to sub-GeV energy and direct the LWFA laser. New LWFAs are now being added to the existing one to accelerate electrons to TeV energies.
Günceleme: 25/05/2023 17:19