Towards spectro-microscopy at extreme limits

This talk is devoted to modern methods for attosecond and femtosecond laser spectro-microscopy with the special focus on applications that require extreme spatial resolution. In the first part, I discuss how high-harmonic generation by high-energy, high-power light transients holds promise to deliver the required photon flux and photon energy for attosecond pump-probe spectroscopy at high spatiotemporal resolution in order to capture electron-dynamic in matter. I demonstrate the first prototype high-energy field synthesizer based on Yb:YAG, thin-disk laser technology for generating high-energy light transients. In the second part of my talk, I show resolving the complex electric field of light at PHz frequency by means of electro-optic sampling in ambient air, and discuss the potential of the technique in molecular spectroscopy and high-resolution, label-free imaging. 1. A. Alismail et al., "Multi-octave, CEP-stable source for high-energy field synthesis," Science Advances 6, eaax 3408 (2020) 2. H. Wang et al., "High Energy, Sub-Cycle, Field Synthesizers," IEEE Journal of Selected Topics in Quantum Electronics, (2019). 3. A. Sommer et al., " Attosecond nonlinear polarization and energy transfer in dielectrics," Nature 534, 86 (2016). 4. H. Fattahi, "Sub-cycle light transients for attosecond, X-ray, four-dimensional imaging," The Contemporary Physics Journal, 57, 1 (2016). 5. H. Fattahi et al., "Third-generation femtosecond technology," Optica 1, 45 (2014).