LASCAR

This project will address the interaction of a single Carbon Cone nanoTip (CCnT) with ultrashort laser pulses leading to electron emission. Several mechanisms can induce the emission depending on the parameters. The control of the electronic properties during the interaction will be driven jointly by the choice of the laser parameters and the design of the CCnT. The latter consists of a carbon cone grown onto a single carbon nanotube (CNT) leading to an apex size of a few nm. This creates a field enhancement and plasmonic effect which will ease the observation of strong-field effects. One goal will be to improve the nanotips field emission properties by using doped and filled CNTs on which cones will be grown to obtain new kinds of CCnTs called meta-CCnTs. Field emission under static field will be systematically studied before laser irradiation and the tip will be systematically characterized by electron microscopy in order to fully control the process. One major purpose will be to understand how the emission occurs at the tip apex. We plan to answer this question through the development of spatial and spectral imaging of the electrons. For strong field phenomena studies, a mid-IR few-cycle high repetition rate laser will be developed in order to reach longer wavelengths leading to higher recollision energies. Harmonic generation will be investigated for the first time on such systems, thanks to the interaction of the CCnT and this laser. The experiments will be accompanied by TDDFT (Time Dependant Density Functional Theory) calculations. Furthermore, novel mixed quantum/classical approaches will be developed, to account for the large amplitude electronic motion, important in the process of high harmonic generation (HHG). This project at the frontier of ultrafast technology and nanosciences, will benefit from the synergy of four partners (LCAR-LPT-CEMES and the University of Zaragoza (ZGZ) which belongs to a joined LEA (Associated European Laboratory) with CEMES). Experimental expertise in ultrafast technologies and quantum control will be given by the LCAR-Femtocontrol group, while the LCAR-“Ion-matter interaction” group will provide the knowledge on the electron detection set-up. The growth, doping, filling and characterization of the CCnTs will be performed jointly by CEMES and ZGZ while theoreticians from LCAR and LPT will perform the theoretical modeling and the numerical simulations. Beyond fundamental issues related to strong field laser-matter interaction, these studies also raise great expectations as they could lead to new applications for these meta-cones and also high brightness electron sources for electron microscopy as well as the development of new microscopy techniques for imaging nanostructures at the few nanometer spatial scale and few femtosecond timescale.