The APPLI group was created in 2013. We combine broad expertise from two different fields of physics: (i) ultrafast dynamics in condensed matter, (ii) and the field of relativistic laser-plasma interaction. We rely on pump-probe experiments with photons and/or electrons as probes for studying the dynamics of matter on very short time scales (femtosecond). With the help of these tools, we attempt to bring new insights into materials such as ultrafast switches, materials for solar energy… At the fundamental level, we are interested in the dynamics of phase transitions in out-of-equilibrium conditions and in the interplay between various degrees of freedom (spins, carriers, lattice) in complex materials.

Half of the group is also dedicating research efforts toward the development of new experimental tools to achieve these goals. In particular, we are developing a new technology called “laser-plasma acceleration” for creating ultrashort pulses of electrons and X-rays. Laser-plasma accelerators are based on the interaction of an ultra-high intensity laser pulse with an underdense plasma. The laser pulse generates plasma waves that accelerate electrons to relativistic energies in micrometer distances, thereby producing femtosecond electron bunches. Our group is currently working on a high-repetition rate laser-plasma accelerator (kHz repetition rate), with parameters relevant for probing materials on atomics spatial and temporal scales.The group is exploring the physics of laser-plasma accelerators as well as its potential applications in ultrafast dynamics but also medical applications.