Resumen de High power, high intensity few-cycle pulses in the mid-ir for strong-field experiments
High-energy, few-cycle, mid-lR radiation sources featuring high pulse repetition rates are of tremendous interest for a variety of strong-field physics and attoscience applications. Such systems could be used in combination with the high harmonic generation process as nolel, tabletop, high-fluxX-rayradiation sources providing photon energies up to the keVlevel.
Additionally, strong-field ionization eperiments of atom and molecules could help unravel the underlying phpics of photochemical reactions and molecular transformations.
Nevertheless, implementing such sources remains challenging due to the absence of suitable mid-lR laser gain materials.
One approach to orcrcome current limitations is optical parametric chirped pulse amplification (OPCPA). While this method is already commonly used in the visible and near-lR spectral range, justfew demonstrations emitting mid-lR, highenergy, few-cple pulses meeting the stringent requirements set by strongfield physics erperiments hare been demonstrated. ln this thesis we present our effort to push the performance of current high-power, m id-lR OPCPA systems to overcome existing limitations and to match and even exceed the performance of similar visible and near-lR radiation sources.
We report on the design and implementation of a high-efficiency, frequency up-con\,ersion extension of the one-of-a-kind, high-power, few-cycle, mid-lR OPCPA system located in the AUO group at the lnstitute of Photonic Sciences in Barcelona.
The unique multi-color source provides opticallysynchronized, high-energy, femtosecond outputs atwavelength ranging from the deep-UV up to the mid-lR regime and a high pulse repetition rate bepnd 100 kHz. The short output pulse durations in combination with the all optical synchronization scheme makes the source a unique tool to drive highly nonlinear and strongfield pump-probe eperiments in the tunnel or multi-photon ionization regime.
ln the second part, we report on the fundamental redesign and rebuild of the original high-power, mid-lR source yielding the first implementation of a GW-lercl peak-power, mid-lR OPCPA system featuring simultaneously pulse repetition rates beyond 100 kHz The upscaling of the pulse energy by a factor of 6 while maintaining the pulse repetition rate yelds a mid-lR output average power of 19 W ln order to enable such large mid-lR average power, we performed an in-depth study of common, nonlinear mid-lR crystals in respect to their thermal, via residual absorption induced parametric amplification limitations.
ln the third part, we present one of the first realizations of few-cycle, mid-lR pulse self-compression via filamentary propagation in the anomalous dispersion regime in a bulk medium. The spectro-temporal behavior of the self-compressed pulses is studied as a function of the driving mid-lR pulse parameters resulting in temporal pulse shortening down to sub-3 optical crycles. We prove the suitabilityof this technique as compactand stable post-compression method featuring CEPstable,few-cycle pulse generation in the mid-lR spectral range.
