The effect of initial phase on the emission characteristics of forward electron colliding with a tightly focused linearly polarized few-cycle laser pulse

Laser Physics ◽  
2021 ◽  
Vol 32 (2) ◽  
pp. 025001
Author(s):  
XingKang Li ◽  
Shuwen Mao ◽  
Penghang Yu ◽  
JianPing Chang ◽  
Youwei Tian
Keyword(s):  
Laser Pulse ◽  
Strong Field ◽  
High Harmonic ◽  
Potential Method ◽  
Harmonic Spectrum ◽  
X Ray ◽  
High Order Harmonic ◽  
Linearly Polarized ◽  
The Time Domain ◽  
The Relationship

Abstract We have studied the high harmonic radiation property from the scattering of an electron with a focused few-cycle laser pulse by analyzing the distribution of the radiation field and the motion state of the electron. In the time domain, temporal width of the compressed radiation can reach 33 zs (zeptosecond), thus an ultrashort x-ray pulse was generated in the interaction process. The radiation in this process is vastly similar to high harmonic generation in the process of atomic strong-field. The latter depends to a large extent on the phase of carrier-envelope (CE) driving laser pulse. The cutoff of radiation spectrum can reach 1 × 10 5 ω 0 , and whether the high-order harmonic spectrum in the cut-off region can be well resolved depends on the CE phase. We have investigated the relationship between the maximum radiation intensity and the CE phase, and discussed a potential method to characterize the CE phase of an intense few-cycle laser pulse for broader application prospects.

scholarly journals Detecting electronic coherences by time-domain high-harmonic spectroscopy

2020 ◽  
Vol 117 (18) ◽  
pp. 9776-9781 ◽  
Author(s):  
Shicheng Jiang ◽  
Konstantin Dorfman
Keyword(s):  
Time Domain ◽  
High Harmonic ◽  
Electronic States ◽  
High Order ◽  
Laser Source ◽  
X Ray ◽  
Liouville Space ◽  
High Order Harmonic ◽  
Multiple Pulses ◽  
The Time Domain

Ultrafast spectroscopy is capable of monitoring electronic and vibrational states. For electronic states a few eV apart, an X-ray laser source is required. We propose an alternative method based on the time-domain high-order harmonic spectroscopy where a coherent superposition of the electronic states is first prepared by the strong optical laser pulse. The coherent dynamics can then be probed by the higher-order harmonics generated by the delayed probe pulse. The high nonlinearity typically modeled by the three-step mechanism introduced by Lewenstein and Corkum can serve as a recipe for generation of the coherent excitation with broad bandwidth. The main advantage of the method is that only optical (non–X-ray) lasers are needed. A semiperturbative model based on the Liouville space superoperator approach is developed for the bookkeeping of the different orders of the nonlinear response for the high-order harmonic generation using multiple pulses. Coherence between bound electronic states is monitored in the harmonic spectra from both first- and second-order responses.

scholarly journals Fully stabilized multi-TW optical waveform synthesizer: Toward gigawatt isolated attosecond pulses

2020 ◽  
Vol 6 (16) ◽  
pp. eaay2802 ◽  
Author(s):  
Bing Xue ◽  
Yuuki Tamaru ◽  
Yuxi Fu ◽  
Hua Yuan ◽  
Pengfei Lan ◽  
...  
Keyword(s):  
Harmonic Spectrum ◽  
Pump Laser ◽  
X Ray ◽  
High Order Harmonic ◽  
Delay Dependence ◽  
Control Scheme ◽  
Active Stabilization ◽  
Waveform Synthesis ◽  
Spectrum Intensity ◽  
The One

A stable 50-mJ three-channel optical waveform synthesizer is demonstrated and used to reproducibly generate a high-order harmonic supercontinuum in the soft x-ray region. This synthesizer is composed of pump pulses from a 10-Hz repetition-rate Ti:sapphire pump laser and signal and idler pulses from an infrared two-stage optical parametric amplifier driven by this pump laser. With full active stabilization of all relative time delays, relative phases, and the carrier-envelope phase, a shot-to-shot stable intense continuum harmonic spectrum is obtained around 60 eV with pulse energy above 0.24 μJ. The peak power of the soft x-ray continuum is evaluated to be beyond 1 GW with a 170-as transform limit duration. We found a characteristic delay dependence of the multicycle waveform synthesizer and established its control scheme. Compared with the one-color case, we experimentally observe an enhancement of the cutoff spectrum intensity by one to two orders of magnitude using three-color waveform synthesis.

scholarly journals Assessment of the LFAs-PBE exchange–correlation potential for high-order harmonic generation of aligned H2+ molecules

RSC Advances ◽  
2016 ◽  
Vol 6 (40) ◽  
pp. 33318-33325 ◽  
Author(s):  
Hsiao-Ling Sun ◽  
Wei-Tao Peng ◽  
Jeng-Da Chai
Keyword(s):  
Laser Pulse ◽  
Harmonic Generation ◽  
High Order ◽  
High Order Harmonic Generation ◽  
Exchange Correlation ◽  
Exchange Correlation Potential ◽  
High Order Harmonic ◽  
Correlation Potential ◽  
Linearly Polarized

We examine the performance of the LFAs-PBE exchange-correlation potential for the HHG spectra and related properties of H2+ molecules aligned parallel and perpendicular to the polarization of an intense linearly polarized laser pulse.

scholarly journals Strong-field coherent control of isolated attosecond pulse generation

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yudong Yang ◽  
Roland E. Mainz ◽  
Giulio Maria Rossi ◽  
Fabian Scheiba ◽  
Miguel A. Silva-Toledo ◽  
...  
Keyword(s):  
Coherent Control ◽  
Strong Field ◽  
High Harmonic ◽  
Pulse Generation ◽  
Photon Flux ◽  
High Order Harmonic ◽  
Isolated Attosecond Pulse ◽  
Attosecond Pulses ◽  
Waveform Synthesis ◽  
Attosecond Science

AbstractAttosecond science promises to reveal the most fundamental electronic dynamics occurring in matter and it can develop further by meeting two linked technological goals related to high-order harmonic sources: improved spectral tunability (allowing selectivity in addressing electronic transitions) and higher photon flux (permitting to measure low cross-section processes). New developments come through parametric waveform synthesis, which provides control over the shape of field transients, enabling the creation of highly-tunable isolated attosecond pulses via high-harmonic generation. Here we demonstrate that the first goal is fulfilled since central energy, spectral bandwidth/shape and temporal duration of isolated attosecond pulses can be controlled by shaping the laser waveform via two key parameters: the relative-phase between two halves of the multi-octave spanning spectrum, and the overall carrier-envelope phase. These results not only promise to expand the experimental possibilities in attosecond science, but also demonstrate coherent strong-field control of free-electron trajectories using tailored optical waveforms.

scholarly journals Quantum interference in strong-field ionization by a linearly polarized laser pulse and its relevance to tunnel exit time and momentum

2021 ◽  
Vol 104 (3) ◽  
Author(s):  
Szabolcs Hack ◽  
Szilárd Majorosi ◽  
Mihály G. Benedict ◽  
Sándor Varró ◽  
Attila Czirják
Keyword(s):  
Laser Pulse ◽  
Quantum Interference ◽  
Strong Field ◽  
Exit Time ◽  
Field Ionization ◽  
Strong Field Ionization ◽  
Linearly Polarized

scholarly journals Attoscience in phase space

2021 ◽  
Vol 75 (7) ◽  
Author(s):  
H. Chomet ◽  
C. Figueira de Morisson Faria
Keyword(s):  
Phase Space ◽  
Harmonic Generation ◽  
Strong Field ◽  
High Harmonic ◽  
High Order ◽  
High Order Harmonic Generation ◽  
High Order Harmonic ◽  
The Subject ◽  
Space Dynamics ◽  
Quantum Correspondence

Abstract We provide a brief review of how phase space techniques are explored within strong-field and attosecond science. This includes a broad overview of the existing landscape, with focus on strong-field ionisation and rescattering, high-order harmonic generation, stabilisation and free-electron lasers. Furthermore, using our work on the subject, which deals with ionisation dynamics in atoms and diatomic molecules as well as high-order harmonic generation in inhomogeneous fields, we exemplify how such tools can be employed. One may for instance determine qualitatively different phase space dynamics, explore how bifurcations influence ionisation and high-harmonic generation, establish for which regimes classical and quantum correspondence works or fails, and what role different timescales play. Finally, we conclude the review highlighting the importance of the tools available in quantum optics, quantum information and physical chemistry to strong-field laser–matter interaction. Graphic Abstract

scholarly journals Interaction of ultra-intense laser pulses with relativistic ions

2004 ◽  
Vol 22 (3) ◽  
pp. 203-206 ◽  
Author(s):  
C.C. CHIRILĂ ◽  
C.J. JOACHAIN ◽  
N.J. KYLSTRA ◽  
R.M. POTVLIEGE
Keyword(s):  
Laser Pulse ◽  
Strong Field ◽  
Ion Beam ◽  
Laser Pulses ◽  
Field Approximation ◽  
High Order ◽  
Intense Laser ◽  
High Order Harmonic ◽  
Intense Laser Pulses ◽  
High Laser

At high laser intensities, three step recollision processes such as high order harmonic generation and high-order ATI, are normally severely suppressed due to the magnetic field component of the laser pulse. However, if the laser pulse and relativistic ion beam are directed against each other, a significant increase in the frequency and the intensity of the pulse in the rest frame of the ions can occur. By performing calculations based on a Coulomb-corrected nondipole strong field approximation, we have shown that there is a range of intensities, Lorentz factors, and ion charges for which the suppression of the three step recollision processes is not severe, even for ponderomotive energies exceeding 10 keV. As an example, we consider parameters relevant to the accelerator that will be built at GSI-Darmstadt, capable of accelerating multicharged ions to Lorentz factors reaching 30.

Sign in / Sign up

Export Citation Format

Share Document