Abstract
High-order harmonic generation, which is a hot topic of strong ultrafast fields, is one of the most important ways for obtaining the ultraviolet attosecond sources, and has a very wide application prospect. This work focuses on the challenges of the generation of either short or high attosecond pulses. We present the research progress of the high-order harmonics and attosecond pulse generation, and propose an effective and feasible method, and show some results. Specifically, combining the time-dependent Schrödinger equation and new unconstrained optimization algorithm, the objective function with the aim of the widest supercontinuum plateau of He atom is designed and the optimized two-color and three-color laser fields are obtained. The supercontinuum spectra extend up to 100 harmonic orders for the case of the optimized two-color laser field. As a result, a single ultrashort attosecond pulse of 25 as is produced. For the three-color case, the supercontinuum spectra reach up to 170 harmonic orders, and the width of single shortest attosecond pulse obtained by superposing pulses from low order (110 order) to high order (280 order) is obtained to be 17 as . Taking the optimized two-color laser field for example, the macroscopic medium propagation is discussed by solving the Maxwell equation. The results show that the selectivity of quantum trajectories from far-field space distribution can obtain the single ultra-short attosecond pulse.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
