Open AccessIsolated 38 as pulse generation from two-color pulse
Author(s) -
Chunqing Gao,
Yu-Jun Yang,
Fei Guo
Publication year - 2013
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.62.073203
Subject(s) - supercontinuum , attosecond , pulse (music) , physics , harmonics , optics , femtosecond pulse shaping , bandwidth limited pulse , high harmonic generation , multiphoton intrapulse interference phase scan , ultrashort pulse , helium atom , laser , harmonic spectrum , atomic physics , helium , quantum mechanics , wavelength , voltage , photonic crystal fiber , detector
We have investigated theoretically the high-order harmonics and attosecond pulse generation by numerically solving the one-dimensional time-dependent Schrödinger equation from a helium atom in a two-color laser field, which is synthesized by adding a 1330-nm infrared pulse with higher intensity to an 800-nm fundamental pulse with lower intensity. Our results clearly show that if the phase difference between the two pulses is selected suitably, the generation of high-order harmonics spectrum with a broadband supercontinuum characteristic can be achieved, and an isolated 38 as pulse can be realized. By the time-frequency analysis, we find that the isolated attosecond pulse comes from the contribution of the long and short quantum paths, and for these two quantum paths the change of emission time with the harmonics order is rather slow. This is different from the traditional isolated attosecond pulse generation that a single quantum path needs to be picked up to obtain an isolated attosecond pulse.