Laser-Plasma-Interaction

Laser driven particle acceleration

Laser driven particle acceleration happens on extremely short spatial scales of micrometres to centimetres. The main interest of our research here is the further understanding of different acceleration processes and the development of new technologies for potential applications, including medicine. For instance, we successfully demonstrated extraordinarily collimated proton beams with the aid of nanometer DLC foils and explored it for radiobiological investigations at MPQ. Future developments will be based on our developing laser systems in Garching with increased laser peak power, but also on improved targets which are being developed in-house.

Study of electron dynamics in (over)dense plasmas

Planar Nano-targets such as DLC foil offer unique properties for studying the motion of electrons in dense plasmas. They can form relativistic mirrors or dense electron sheets for generating ultraviolet radiation with sub-fs duration. Most importantly, however, it is the electrons dynamics which determines the functionality and efficiency of ion acceleration with high intensity laser pulses.

Development of advanced optical diagnostic methods for relativistic laser plasma
physics

Optical diagnostic techniques are essential for a reliable and efficient operation and control of our laser plasma sources. Moreover they also represent powerful tools to shed light onto the underlying physical processes revealing crucial plasma parameters like electron densities with unprecedented accuracy and resolution in space and time. Novel ultrafast time-resolved experimental techniques imaging the plasma evolution are under development as well as focus optimization and monitoring systems. Additionally automated feedback control over relevant laser parameters via auto focusing and alignment should be achieved. Ultimately those techniques will result in improved and more stable ion acceleration, e.g. by better control of the laser contrast at the target via optimized plasma mirrors. Aiming forbiomedical applications online monitoring of the source is a key feature. In addition, those techniques are a step stone for studies in ultrafast interaction of charged particles with (biological) matter.

Fully isolated dense plasmas

The investigation of isolated, levitating targets with extensions similar to the lase focal spot is enabled by Paul-trap technology. It allows detailed studies of the interaction of laser pulses with dense plasmas in a nearly closed system and will provide a unique test ground for the generation of fast particles and radiation.

Numerical simulations

Particle-in-cell (PIC) simulations are a standard tool in laser plasma physics. We utilize a variety of 1, 2 and 3D codes, including PSC (H. Ruhl) and KLAP (X. Yan).