The research work is investigating plasma amplification, which could be a way to overcome the limitations of solid-state optical materials as far as the damage threshold is concerned. Plasma can sustain much higher energy fluxes than standard optics and will allow eventually to amplify light pulses to power levels beyond 10 PW. In particular the team with Stefan Weber from ELI Beamlines was investigating spectral characteristics of the amplified pulse in order to better understand and control the amplification process.