XUV pulse effect on harmonic emission spectra and attosecond pulse generation

The generation of the high-order harmonic and the attosecond pulse from He atom driven by the near-infrared (NIR) field combined with the XUV pulse has been theoretically investigated by solving the three-dimensional time-dependent Schrödinger equation. The results show that by properly adding the XUV pulse into the NIR field, (i) not only the harmonic yield is enhanced, caused by the laser-induced excited state effect; but also the multi-cutoff extension of the harmonics can be found, caused by the absorption of the extra XUV photons during its recombination process. (ii) With the introduction of the XUV pulse, the frequency modulation of the high-order harmonic generation (HHG) can be found and controlled. (iii) By directly superposing the harmonics in the cutoff region, two isolated XUV pulses with the durations of 150 as can be obtained.

Download Full-text

Two states hydrogenlike model for high-order harmonic generation and an isolated attosecond pulse generation in a He+ ion

Optics Communications ◽

10.1016/j.optcom.2012.11.063 ◽

2013 ◽

Vol 296 ◽

pp. 113-123 ◽

Cited By ~ 17

Author(s):

Masoud Mohebbi ◽

Saeed Batebi

Keyword(s):

Harmonic Generation ◽

Pulse Generation ◽

Attosecond Pulse ◽

High Order ◽

High Order Harmonic Generation ◽

High Order Harmonic ◽

Isolated Attosecond Pulse ◽

Attosecond Pulse Generation

Download Full-text

Initial state effect on waveform control of high-order harmonic spectrum and attosecond pulse generation

Modern Physics Letters B ◽

10.1142/s0217984921503668 ◽

2021 ◽

pp. 2150366

Author(s):

Hang Liu ◽

Xiaodan Jing ◽

Yan Qiao ◽

John McCain ◽

Liqiang Feng

Keyword(s):

Harmonic Spectrum ◽

Pulse Generation ◽

Attosecond Pulse ◽

High Order ◽

High Order Harmonic Generation ◽

Initial State ◽

High Order Harmonic ◽

Waveform Control ◽

Attosecond Pulses ◽

Attosecond Pulse Generation

In this paper, the waveform control of high-order harmonic generation and attosecond pulse generation from a different initial state of He atom has been investigated. The results show that (i) by properly controlling the carrier-envelope phases, the time delays and the laser intensities of a 3-color laser pulse, the best waveforms for the harmonic cut-off extension can be found. Although the harmonic cut-offs from the ground initial state and the superposition initial state are almost the same, the harmonic intensities from the superposition initial state are 4 to 5 orders of magnitudes higher than those from the ground initial state. (ii) With the introduction of the inhomogeneous effect, the harmonic cut-offs can be further extended. However, the harmonic intensities from the superposition initial state are remarkably decreased compared with those from the homogeneous pulses, which is unbeneficial to generate the intense attosecond pulses. (iii) When the ground state is chosen to be the initial and with the assistance of the 4th UV pulse, not only the larger harmonic cut-offs can be obtained, but also the stronger harmonic plateaus can be found, which is favorable for producing the intense attosecond pulses. Thus, at the end of this paper, by superposing the harmonics from the best harmonic spectra, the single attosecond pulses with the duration of 36 as can be obtained.

Download Full-text

QUANTUM WAVE-PACKET EXPLORATION OF ISOLATED ULTRA-SHORT ATTOSECOND PULSE GENERATION BY A MODIFIED THREE-COLOR LASER FIELD SCHEME

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633612500988 ◽

2013 ◽

Vol 12 (01) ◽

pp. 1250098

Author(s):

YUNHUI WANG ◽

HAIPING WU ◽

CHAO YU ◽

QI SHI ◽

KAIMING DENG ◽

...

Keyword(s):

Laser Field ◽

Three Dimensional ◽

Pulse Generation ◽

Attosecond Pulse ◽

Time Dependent ◽

High Order Harmonic ◽

Quantum Wave ◽

Attosecond Pulse Generation ◽

Color Field ◽

Harmonic Conversion

By numerically solving the three dimensional time-dependent Schrödinger equation, we explore the high-order harmonic and attosecond pulse generation of He atoms exposed to a special three-color field. An ultrabroad supercontinuum with a bandwidth of 887 eV has been attained, supporting an isolated 4 as pulse straightforwardly by Fourier transforming. Utilizing available intense infrared femtosecond laser resource within the nonrelativistic regime, the produced laser pulse is near to zeptosecond region. Remarkably, the harmonic conversion efficiency is enhanced in terms of the double-plateau structure of the harmonic spectra, yielding high-intensity attosecond pulses with alternative plateau.

Download Full-text