High power lasers can be focused to intensities > 1e18 W/cm2 and used to irradiate solid targets to generate plasma. At these ultra-intensities the electrons are relativistically accelerated by the laser fields into the target as “fast electrons”. The generation and transport of these fast electrons drives proton acceleration, X-ray generation, and the formation of warm and hot dense matter relevant for laboratory astrophysics studies for example. The laser can only propagate in the plasma target up to the “critical density” which restricts absorption to the front surface. One approach to enhance absorption is to use nanowire targets where it has been shown that fast electron temperature and numbers are increased.