Multiple high-order harmonic generation in the presence of intense laser and static magnetic fields
Journal
Journal of Physics B: Atomic, Molecular and Optical Physics
Journal Volume
32
Journal Issue
23
Pages
5593-5603
Date Issued
1999
Author(s)
Tong, X.M.
Abstract
We perform a nonperturbative study of the effect of static magnetic fields on the multiple high-order harmonic generation (HHG) processes of atomic H in intense pulsed laser fields. The time-dependent Schrödinger equation in three spatial dimensions can be solved accurately and efficiently by means of the recently developed time-dependent generalized pseudospectral method (Tong XM and Chu S I 1997 Chem. Phys. 217 119). We found that the presence of a static magnetic field perpendicular to the laser field polarization direction can introduce a second HHG plateau, allowing significant extension of the cut-off. The high harmonics in the second plateau reach a maximum enhancement when the cyclotron frequency of the electron is about equal to one half of the laser frequency. Through a detailed time-frequency wavelet analysis of the HHG spectra, we have identified a `synchrotron radiation'-like new mechanism responsible for the production of the second plateau.
SDGs
Type
journal article