Probing the spatio-temporal properties of strong field harmonic emission in the liquid phase

• Applicant: Professor Dr. Milutin Kovacev
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2012 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 210192221

The study of non-perturbative phenomena in atomic systems has become a vivid field of research during the last decade. In particular coherent and strong field-matter interactions such as the generation of XUV radiation through high-order harmonic generation (HHG) and its attosecond time structure are of sound interest. Only recently, the attention has turned towards the investigation of HHG in more complex systems like molecules, clusters in the gas phase and surfaces. Largely unexplored is still the liquid phase in the strong field-matter interaction context.The goal of this proposal is to study in detail the non-perturbative process of HHG in liquid water droplets experimentally. In particular the investigation of the underlying generation mechanism, the scaling laws and the efficiency of the process using coherent control of electromagnetic fields is of great interest. In a second step the controlled embedding of nanoparticles in the liquid water matrix will be conducted in order to investigate and tailor the harmonic emission characteristics. Loading the droplets with nanoparticles allows for an investigation of the quantum confinement effect. Minimizing the particle size can therefore lead to an increase of the maximum photonic energy due to an increasing band-gap within the particle. High-harmonic spectroscopy will then serve to study the spatio-temporal properties of the nanoparticles. Finally, we aim to develop a readily available experimental technique that can then be used in numerous applications.

• DFG Programme: Research Grants