Laser-plasma acceleration is now entering an era of petawatt lasers, tenuous plasmas and multi-GeV electron energies. I will review initial results in this regime obtained with the Texas Petawatt laser, which has accelerated self-injected electrons from tenuous plasma quasi-monoenergetically up to 2 GeV with unprecedented sub-milliradian angular divergence, producing bright 20 keV betatron x-rays as a by-product [1]. Yet this is only the beginning. Simulations predict that petawatt pulses of currently available parameters can accelerate electrons quasi-monoenergetically up to at least 10 GeV with negligible dark current [2].Such an accelerator can provide the basis of a new generation of table-top x-ray free electron lasers for university-based biochemical and physical research [3]. Optimized accelerator performance depends critically on spatio-temporal structure of the plasma wave. I will discuss advanced plasma diagnostics that enable 4D spatio-temporal visualization of the plasma structure and accelerating electrons that will be critical to understanding, optimizing and scaling multi-GeV laser-plasma accelerators [4].

[1] X. Wang et al., “Quasi-monoeneretic laser-plasma acceleration of electrons to 2 GeV,” Nature Communications, in press (2013).

[2] W. Lu et al., “Generating multi-GeV electron bunches using single stage laser wakefield acceleration in a 3D nonlinear regime,” Phys. Rev. Spec. Topics – Accel. and Beams 10, 061301 (2011). 

[3] K. Nakajima, “Towards a table-top x-ray free-electron laser,” Nature Physics 4, 92 (2008).

[4] N. H. Matlis et al., “Snapshots of laser wakefields,” Nature Physics 2, 749 (2006).