Nanostructured intense-laser cleaner
  A nanostructured target is proposed to enhance an intense-laser contrast: when a laser prepulse irradiates a nanostructured solid target surface, the prepulse is absorbed effectively by the nanostructured surface. The nanostructure size should be less than the laser wavelength. After the prepulse absorption, the front part of the main pulse destroys the microstructure and makes the surface a flat plasma mirror. The body of the main pulse is reflected almost perfectly. Compared with conventional plasma mirrors, the nanostructured surface is effective for the absorption of the intense laser prepulse, whose intensity is higher than 10^14 W/cm2. The nanostructured laser cleaner improves the laser pulse contrast by about a hundredfold. The nanostructured laser cleaner works well for next-generation intense lasers. 
Xiao Feng Li, Shigeo Kawata, Qing Kong, Ping Xiao Wang, Qin Yu, Yan   Jan Gu and Jun Fan Qu
physics.plasm-ph physics.optics