Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

Plasmas driven by intense, ultra-short laser pulses can support electrical field strengths of up to TV/m, making this concept promising for compact particle accelerators in which ions can gain MeV energies on a micrometer scale. For the acceleration, the laser pulse is focused onto a thin target which quickly ionized and transformed into a plasma in which electrons gain MeV energies in the laser field. These electrons leave the target volume and thereby create quasi-static charge-separation fields along the target surfaces in which the ion acceleration takes place. The acceleration is strongly influenced by the plasma conditions at the target during the main pulse interaction, which are determined by light preceding the intense main pulse or by the rising edge of the main pulse itself.

In this talk, we present a reflective pump probe method which allows to temporally resolve the lateral and longitudinal expansion of the critical plasma density. First experimental results with a pure imaging technique will be shown, in which the front and rear surface plasma were characterized. This technique is currently developed to include interferometry, in that way increasing the sensitivity in longitudinal direction. We will discuss the simulation results and a corresponding experimental setup.