Electron recollision in an intense laser field gives rise to a variety of phenomena, ranging from electron diffraction to coherent soft X-ray emission. We have, over the years, developed intense sources of waveform-controlled mid-IR light to exploit the process with respect to ponderomotive scaling, quantum diffusion and quasi-static photoemission. I will describe how we leverage these aspects to “teach” molecules to take a selfie while undergoing structural change. This permits visualizing for the first time, with combined attosecond temporal and atomic spatial resolution, molecular bond breaking and deprotonation. Furthermore, we achieve isolated attosecond pulses in the soft X-ray water window across the oxygen edge at 543 eV. Accomplishing ultrafast temporal resolution in combination with the soft X-ray’s element specificity now provides an entirely new view on the combined electronic and nuclear dynamics in real time. I will show first results in which we resolve the carrier dynamics in a semimetal in real time.
These results provide first insight into the dynamics of molecules and condensed matter, with the future possibility to address fundamental challenges such as molecular isomerization, phase transitions and superconductivity.