Nonlinear Pulse Compression
Ever more demanding applications require higher and higher peak powers of the driving laser pulse. To increase a lasers pulse‘s peak power beyond what is supported by the laser gain medium itself we develop efficient post-compression schemes. They enable pulse duration compression all the way down to the extreme regime where the pulse energy is squeezed into a temporal slice that lasts only a few cycles of the oscillating laser field. Post-compression is typically achieved in two steps: First, the spectrum of the laser pulse is broadened via non-linear material interaction. Approximately, the spectral broadening step leaves the pulse duration unaffected. Second, all the new spectral components are tuned to oscillate in phase, which results in a pulse with shorter pulse duration. In order to efficiently drive the broadening step, the non-linear interaction is realized while propagating in a quasi-waveguiding structure. For the Millijoule pulse energies we are aiming for, this can be a noble-gas filled capillary or a noble-gas filled multi-pass cell.