Analysis of shockwave formation in glass welding by ultra-short pulses

This is the authors' abstract. We don't add key points for this paper.

Glass welding by ultra-short pulsed lasers is temporally a highly dynamic process. These dynamics have a high impact on the shape and the thermodynamic properties of the molten zone as well as the plasma. In this work we analyze the local distribution of laser absorption in the melt by shockwave observation and the evolution of the subsequent pressure wave generated during the process. The pressure waves were observed using a pump-probe setup with a high-speed video camera. Furthermore we show a dramatic decrease of pressure waves propagation velocity inside the molten zone as an explicit indicator of the fluid state of the molten zone.