Enhancement on Laser Intensity and Proton Acceleration Using Micro-tube   Plasma Lens Targets
  A hollow cylindrical micron-scale structure is proposed to enhance and manipulate the laser plasma interaction. It is shown through 3-D particle-in-cell simulations that the incident laser pulse intensity is enhanced within the tube. A detailed study of the intensification optimizes the tube dimensions and provides a characterization of the in-tube intensity. By coupling the micro-tube plasma lens to a traditional flat interface, we show an increase in on-target intensity. We detail proton energy enhancement as a potential application of the micro-tube plasma lens target, where the tube structure acts to focus the light and provide additional electrons that enhance the accelerating sheath field. 
Joseph Snyder, Liangliang Ji, Kramer Akli
physics.plasm-ph