Laser Beams in Plasma

Low Divergence Laser-plasma-based Beams

We discuss the mechanisms, applications, and extraction of low-divergence laser-plasma-based electron beams that represent our past, current, and future research activities in the Center for Ultrafast Optical Science at the University of Michigan. We show experimentally that these beams have superior transverse emittance of 0.06 pi mm•mrad, along with nC charge, suitable for various application...

Dense monoenergetic proton beams from chirped laser-plasma interaction.

Interaction of a frequency-chirped laser pulse with single protons and a hydrogen gas target is studied analytically and by means of particle-in-cell simulations, respectively. The feasibility of generating ultraintense (10(7) particles per bunch) and phase-space collimated beams of protons (energy spread of about 1%) is demonstrated. Phase synchronization of the protons and the laser field, gu...

Excitation of accelerating plasma waves by counter-propagating laser beams

Generation of accelerating plasma waves using two counter-propagating laser beams is considered. Colliding-beam accelerator requires two laser pulses: the long pump and the short timing beam. We emphasize the similarities and differences between the conventional laser wakefield accelerator and the colliding-beam accelerator (CBA). The highly-nonlinear nature of the wake excitation is explained ...

Parametric excitations of fast plasma waves by counterpropagating laser beams.

Short- and long-wavelength plasma waves can become strongly coupled in the presence of two counterpropagating laser pump pulses detuned by twice the cold-plasma frequency omega(p). What makes this four-wave interaction important is that the growth rate of the plasma waves occurs much faster than in the more obvious copropagating geometry.

Laser-generated ultrasonic beams.