Grant: Discovery Grants Program - Individual

Strong field and attosecond (asec) physics has emerged from atomic and molecular physics; two of the main processes are ionization and high harmonic generation (HHG). Electrons are ionized and quiver in the laser field; upon recollision with their parent ion, a harmonic photon is emitted. Harmonics are emitted in sub-half-cycle laser bursts with a duration on the attosecond (1asec=10-18s) time scale. This is the natural time scale of bound electrons moving in atoms and molecules, thus allowing time resolved imaging of electrons, a development which was awarded the Nobel prize in physics 2023. Over the past few years asec physics has crossed boundaries into (i) condensed matter physics, (ii) quantum optics, and (iii) nano-photonics. My proposal centers on new research opportunities in these areas. (i) Condensed matter physics. The discovery of HHG in solids has opened the possibility of all-optical imaging of bandstructure and time-resolved imaging of many-body processes, such as charge and bandgap renormalization during photoexcitation. Our research will improve and develop novel ways of imaging and ultrafast probing of materials. This will result in a better understanding of material properties and thus in an improvement of (opto-)electronic and magnetic devices for information technology. (ii) Quantum optics. HHG has so far been viewed as a classical process. Recent work has shown that harmonic fields acquire quantum properties when driven with quantum fields, such as squeezed state fields. We will work on quantum engineering ionization and HHG with combined quantum and classical fields. This will develop a new platform for high-frequency, high-field quantum sensing, offering improved spatial resolution, atomic and chemical sensitivity, and measurement accuracy. (iii) Nano-photonics. Ionization from nano-tips creates asec electron bursts. This is of substantial interest as a source for asec electron microscopy and for petaherz (PHz) electronics. HHG in solids, enhanced with nanostructures, is expected to lead to the realization of the next generation of ultra-compact XUV light sources, which could be applied to for example, scanning attosecond microscopy. We will apply state of the art calculations to optimize both. Enabling attosecond microscopy and PHz electronics will result in novel imaging methods for materials and life sciences and in a new generation of high speed electronics; this will benefit society. HQP in the three projects will be trained in broad areas of quantum science and engineering, ranging from quantum and nonlinear optics, to materials and nano science. Cross-fertilization between the three projects will ensure a broader training of students. Collaboration with experimentalists will ensure relevance of research and training. All three topics are on the research forefront and will produce high level publications, thus giving HQP a good start into a research career in industry and academia.