Probing spectral and temporal resolved dynamics in high-order harmonic generation of atom driven by multicycle near-infrared laser pulses. (29th September 2020)

• Record Type: Journal Article
• Authors: Han, Lin; Li, Peng-Cheng; Chu, Shih-I
• Is Part Of: Laser physics letters. Volume 17:Number 11(2020:Nov.)
• Publication Date: 2020-09-29
• Subjects: high-order harmonic generation -- quantum trajectories -- synchrosqueezed transform -- strong field laser physics; Lasers -- Periodicals; Physics -- Periodicals; 621.366
• DOI: 10.1088/1612-202X/abb40a
• Languages: English
• ISSNs: 1612-2011

Abstract

Abstract: We present an ab initio investigation of the time-frequency characteristics of high-order harmonic generation (HHG) calculated by solving accurately and efficiently the time-dependent Schrödinger equation by means of the time-dependent generalized pseudospectral method. We extend a new synchrosqueezing transform (SST) to obtain the time-frequency spectra of the HHG and the dynamical phase associated with the dipole-emission time profile. The SST time-frequency analysis allows us to explore in depth the dynamics and contributions of the quantum trajectories in HHG. Particularly it uncovers the subtle details of the spectral and temporal fine structures of the HHG and provides novel insights regarding the dynamical origin of the HHG in below-threshold harmonic regimes.