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Double Ionization Dynamics of Molecular Hydrogen in Ultrashort Intense Laser Fields
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作者 陈永菊 余少刚 +5 位作者 孙仁平 龚成 华林强 赖炫扬 全威 柳晓军 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第4期24-27,共4页
We experimentally investigate the double ionization pulses. The total kinetic energy release of the two of molecular hydrogen subjected to ultrashort intense laser coincident H+ ions, which provides a diagnosis of di... We experimentally investigate the double ionization pulses. The total kinetic energy release of the two of molecular hydrogen subjected to ultrashort intense laser coincident H+ ions, which provides a diagnosis of different processes to double ionization of H2, is measured for two different pulse durations, i.e., 25 and 5 fs, and various laser intensities. It is found that, for the long pulse duration (i.e., 25 fs), the double ionization occurs mainly via two processes, i.e., the charge resonance enhanced ionization and recollision-induced double ionization. Moreover, the contributions from these two processes can be significantly modulated by changing the laser intensity. In contrast, for a few-cycle pulse of 5 fs, only the recollsion-induced double ionization survives, and in particular, this process could be solely induced by the first-return reeollision at appropriate laser intensities, providing an efficient way to probe the sub-laser-cycle molecular dynamics. 展开更多
关键词 of IS AS IT Double Ionization Dynamics of Molecular Hydrogen in Ultrashort intense laser fields for in
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Charge Resonance Enhanced Multiple Ionization of H2O Molecules in Intense Laser Fields
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作者 刘鸿 黎敏 +5 位作者 解西国 吴聪 邓勇开 吴成印 龚旗煌 刘运全 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期43-47,共5页
We perform a kinetically complete measurement on the fragmentation of Coulomb explosion of 1-120 molecules in intense few-cycle linearly and circularly polarized laser fields. Both the fragmentations of 1t203+ and H... We perform a kinetically complete measurement on the fragmentation of Coulomb explosion of 1-120 molecules in intense few-cycle linearly and circularly polarized laser fields. Both the fragmentations of 1t203+ and H204+ reveal the concerted pathway of dissociation. The length of the OH bond prior to the Coulomb explosion of both molecular ions is sensitive to the laser pulse duration and laser intensity. However, the bending angle of H-O-H is less sensitive to the pulse duration and laser intensity. We introduce the mechanism of charge resonance enhanced double ionization to elucidate the triple (or quadruple) dissociative ionization dynamics of H20, in which two electrons are non-adiabatically localized at the protons of the precursor ion H2O^+ (or H2O^2+) and are released simultaneously due to the over barrier ionization in the combined laser field and molecular ionic potential. Such charge resonance enhanced multiple ionization is not suppressed in few-cycle laser fields and elliptically polarized laser fields. 展开更多
关键词 In LENGTH Charge Resonance Enhanced Multiple Ionization of H2O Molecules in intense laser fields
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Elliptically polarized high-order harmonic generation of Ar atom in an intense laser field
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作者 胡杰 王一琛 +6 位作者 景秋霜 姜威 王革文 赵逸文 肖礴 梁红静 马日 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期453-457,共5页
High-order harmonic generation(HHG) of Ar atom in an elliptically polarized intense laser field is experimentally investigated in this work.Interestingly,the anomalous ellipticity dependence on the laser ellipticity(... High-order harmonic generation(HHG) of Ar atom in an elliptically polarized intense laser field is experimentally investigated in this work.Interestingly,the anomalous ellipticity dependence on the laser ellipticity(ε) in the lower-order harmonics is observed,specifically in the 13rd-order,which displays a maximal harmonic intensity at ε ≈ 0.1,rather than at ε = 0 as expected.This contradicts the general trend of harmonic yield,which typically decreases with the increase of laser ellipticity.In this study,we attribute this phenomenon to the disruption of the symmetry of the wave function by the Coulomb effect,leading to the generation of a harmonic with high ellipticity.This finding provides valuable insights into the behavior of elliptically polarized harmonics and opens up a potential way for exploring new applications in ultrafast spectroscopy and light–matter interactions. 展开更多
关键词 high-order harmonic generation Coulomb effect elliptically polarized intense laser field
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The dissociation pathways of N_2^+ in intense femtosecond laser fields 被引量:2
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作者 陈德应 张盛 夏元钦 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期3073-3078,共6页
Using a neutral N2 beam as target, this paper studies the dissociation of N2^+ in intense femtosecond laser fields (45 fs, ~ 1 × 10^16 W/cm^2) at the laser wavelength of 800 nm based on the time-of-flight mas... Using a neutral N2 beam as target, this paper studies the dissociation of N2^+ in intense femtosecond laser fields (45 fs, ~ 1 × 10^16 W/cm^2) at the laser wavelength of 800 nm based on the time-of-flight mass spectra of N+ fragment ions. The angular distributions of N^+ and the laser power dependence of N^+ yielded from different dissociation pathways show that the dissociation mechanisms mainly proceed through the couplings between the metastable states (A, B and C) and the upper excited states of N^+.A coupling model of light-dressed potential energy curves of N2^+ is used to interpret the kinetic energy release of N^+. 展开更多
关键词 dissociation mechanisms intense femtosecond laser fields time-of-flight mass spectra
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Observation of the optical X2Σg+–A2Πu coupling in N2+ lasing induced by intense laser field 被引量:1
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作者 Siqi Wang Yao Fu +4 位作者 Danwen Yao Shanming Chen Wei Zhang Helong Li Huailiang Xu 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第12期33-37,共5页
We propose a simple pump-coupling-seed scheme to examine the optical X^2Σg^+–A^2Πu coupling in N2^+ lasing. We produce the N2^+ lasing at 391 nm, corresponding to the B^2Σu^+(v = 0)–X^2Σg+(v = 0) transition, by ... We propose a simple pump-coupling-seed scheme to examine the optical X^2Σg^+–A^2Πu coupling in N2^+ lasing. We produce the N2^+ lasing at 391 nm, corresponding to the B^2Σu^+(v = 0)–X^2Σg+(v = 0) transition, by externally seeding the N^2+ gain medium prepared by irradiation of N2 with an intense pump pulse. We then adopt a weak coupling pulse in between the pump and seed pulses, and show that the intensity of the 391-nm lasing can be efficiently modulated by varying the polarization direction of the coupling pulse with respect to that of the pump pulse. It is found that when the polarization directions of the pump and coupling pulses are perpendicular, the 391-nm lasing intensity is more sensitive to the coupling laser energy, which reflects the inherent nature of the perpendicular X^2+Σg^–A^2Πu transition. 展开更多
关键词 air lasing intense laser fields nitrogen molecules
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Theoretical study of the influence of intense femtosecond laser field on the evolution of the wave packet and the population of NaRb molecule 被引量:5
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作者 马宁 王美山 +2 位作者 杨传路 马晓光 王德华 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第2期213-218,共6页
Employing the two-state model and the time-dependent wave packet method, we have investigated the influences of the parameters of the intense femtosecond laser field on the evolution of the wave packet, as well as the... Employing the two-state model and the time-dependent wave packet method, we have investigated the influences of the parameters of the intense femtosecond laser field on the evolution of the wave packet, as well as the population of ground and double-minimum electronic states of the NaRb molecule. For the different laser wavelengths, the evolution of the wave packet of 6{ }^1/Sigma ^ + state with time and internuclear distance is different, and the different laser intensity brings different influences on the population of the electronic states of the NaRb molecule. One can control the evolutions of wave packet and the population in each state by varying the laser parameters appropriately, which will be a benefit for the light manipulation of atomic and molecular processes. 展开更多
关键词 intense femtosecond laser field time-dependent wave packet method wave packet POPULATION
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Influence of laser fields on the vibrational population of molecules and its wave-packet dynamical investigation 被引量:4
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作者 王军 刘芳 +4 位作者 岳大光 赵娟 许燕 孟庆田 Liu Wing-Ki 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期193-202,共10页
The time-dependent wave packet method is used to investigate the influence of laser-fields on the vibrational population of molecules. For a two-state system in laser fields, the populations on different vibrational l... The time-dependent wave packet method is used to investigate the influence of laser-fields on the vibrational population of molecules. For a two-state system in laser fields, the populations on different vibrational levels of the upper and lower electronic states are given by wavefunctions obtained by solving the Schrbdinger equation with the split- operator method. The calculation shows that the field parameters, such as intensity, wavelength, duration, and delay time etc. can have different influences on the vibrational population. By varying the laser parameters appropriately one can control the evolution of wave packet and so the vibrational population in each state, which will benefit the light manipulation of atomic and molecular processes. 展开更多
关键词 intense laser field time-dependent wave packet method light-matter interaction vibrational population
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Multiphoton and tunneling ionization of atoms in an intense laser field 被引量:1
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作者 付妍卓 赵松峰 周效信 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期167-171,共5页
We study the ionization probabilities of atoms by a short laser pulse with three different theoretical methods, i.e., the numerical solution of the time-dependent SchrSdinger equation (TDSE), the Perelomov-Popov Ter... We study the ionization probabilities of atoms by a short laser pulse with three different theoretical methods, i.e., the numerical solution of the time-dependent SchrSdinger equation (TDSE), the Perelomov-Popov Terent'ev (PPT) theory, and the Ammosov-Delone-Krainov (ADK) theory. Our results show that laser intensity dependent ionization probabilities of several atoms (i.e., H, He, and Ne) obtained from the PPT theory accord quite well with the TDSE results both in the multiphoton and tunneling ionization regimes, while the ADK results fit well to the TDSE data only in the tunneling ionization regime. Our calculations also show that laser intensity dependent ionization probabilities of a H atom at three different laser wavelengths of 600 nm, 800 nm, and 1200 nm obtained from the PPT theory are also in good agreement with those from the TDSE, while the ADK theory fails to give the wavelength dependence of ionization probability. Only when the laser wavelength is long enough, will the results of ADK be close to those of TDSE. 展开更多
关键词 intense laser field ionization probability multiphoton ionization theory
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Quantum Path Selection and Isolated-Attosecond-Pulse Generation of H2+ with an Intense Laser Pulse and a Static Field 被引量:1
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作者 苗向阳 刘莎莎 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第1期42-46,共5页
We theoretically investigate the high-order-harmonic generation from the H2^+ molecular ion exposed to the combi- nation of an intense trapezoidal laser and a static field. The results show that the harmonic spectrum... We theoretically investigate the high-order-harmonic generation from the H2^+ molecular ion exposed to the combi- nation of an intense trapezoidal laser and a static field. The results show that the harmonic spectrum is obviously extended and the short quantum path is selected to contribute to the spectrum, because the corresponding long path is seriously suppressed. Then the combined Coulomb and laser field potentials and the time-dependent electron wave packet distributions are applied to illustrate the physical mechanism of high-order harmonic gen- eration. Finally, by adjusting the intensity of the static field and superposing a properly selected range of the HHG spectrum, a 90-as isolated attosecond pulse is straightforwardly obtained. 展开更多
关键词 Quantum Path Selection and Isolated-Attosecond-Pulse Generation of H2 with an intense laser Pulse and a Static Field
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Measuring gravitational effect of superintense laser by spin-squeezed Bose-Einstein condensates interferometer
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作者 Eng Boon Ng C.H.Raymond Ooi 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第5期265-273,共9页
We consider an extremely intense laser,enclosed by an atom interferometer.The gravitational potential generated from the high-intensity laser is solved from the Einstein field equation under the Newtonian limit.We com... We consider an extremely intense laser,enclosed by an atom interferometer.The gravitational potential generated from the high-intensity laser is solved from the Einstein field equation under the Newtonian limit.We compute the strength of the gravitational force and study the feasibility of measuring the force by the atom interferometer.The intense laser field from the laser pulse can induce a phase change in the interferometer with Bose-Einstein condensates.We push up the sensitivity limit of the interferometer with Bose-Einstein condensates by spin-squeezing effect and determine the sensitivity gap for measuring the gravitational effect from intense laser by atom interferometer. 展开更多
关键词 intense laser field atom interferometer Bose-Einstein condensates spin-squeezing
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High-order harmonic generation spectrum of an excited one-dimensional Coulomb atom in an intense laser field
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作者 周兆妍 袁建民 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第3期675-679,共5页
Response of the wave packet of a one-dimensional Coulomb atom to an intense laser field is calculated using the symmetrized split operator fast Fourier method. The high-order harmonic generation (HHG) of the initial... Response of the wave packet of a one-dimensional Coulomb atom to an intense laser field is calculated using the symmetrized split operator fast Fourier method. The high-order harmonic generation (HHG) of the initial state separately being the ground and excited states is presented. When the hardness parameter a in the soft Coulomb potential V(x) =-1√x^2+α is chosen to be small enough, the so-called hard Coulomb potential V(x)=1/|x| can be obtained. It is well known that the hard one-dimensional Coulomb atom has an unstable ground state with an energy eigenvalue of - 0.5 and it has no states corresponding to physical states in the true atoms, and has the first and second excited states being degenerate. The parity effects on the HHG can be seen from the first and second excited states of the hard one-dimensional Coulomb atom. The HHG spectra of the excited states from both the soft and hard Coulomb atom models are shown to have more complex structures and to be much stronger than the corresponding HHG spectrum of the ground state of the soft Coulomb model with a = 2 in the same laser field. Laser-induced non-resonant one-photon emission is also observed. 展开更多
关键词 high order harmonic generation intense laser field one-dimensional Coulomb atom
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Controlling Three-Dimensional Electron-Electron Correlation via Elliptically Polarized Intense Laser Field
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作者 Jian-Xing Hao Xiao-Lei Hao +2 位作者 Wei-Dong Li Shi-Lin Hu Jing Chen 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第4期30-34,共5页
The three-dimensional electron-electron correlation in an elliptically polarized laser field is investigated based on a semiclassical model. Asymmetry parameter α of the correlated electron momentum distribution is u... The three-dimensional electron-electron correlation in an elliptically polarized laser field is investigated based on a semiclassical model. Asymmetry parameter α of the correlated electron momentum distribution is used to quantitatively describe the electron-electron correlation. The dependence of α on elliptieity e is totally different in three directions. For the z direction (maJor polarization direction), α first increases and reaches a maximum at ε = 0.275, then it decreases quickly. For the y direction in which the laser field is always absent, the ellipticity has a minor effect, and the asymmetry parameter fluctuates around α = -0.15. However, for the x direction (minor polarization direction), α increases monotonously with ellipticity though starts from the same value as in the y direction when ε = 0. The behavior of α in the x direction actually indicates a transformation from the Coulomb interaction dominated correlation to the laser field dominated correlation. Therefore, our work provides an efficient way to control the three-dimensional electron electron correlation via an elliptically polarized intense laser field. 展开更多
关键词 Controlling Three-Dimensional Electron-Electron Correlation via Elliptically Polarized intense laser Field RII
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Structural deformation of nitro group of nitromethane molecule in liquid phase in an intense femtosecond laser field
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作者 王畅 吴红琳 +1 位作者 宋云飞 杨延强 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期228-233,共6页
The structural deformation of NO2 group induced by an intense femtosecond laser field of liquid nitromethane(NM)molecule is detected by time-and frequency-resolved coherent anti-Stokes Raman spectroscopy(CARS) tec... The structural deformation of NO2 group induced by an intense femtosecond laser field of liquid nitromethane(NM)molecule is detected by time-and frequency-resolved coherent anti-Stokes Raman spectroscopy(CARS) technique with the intense pump laser. Here, we present the mechanism of molecular alignment and deformation. The CARS spectra and its FFT spectra of liquid NM show that the NO2 torsional mode couples with the CN symmetric stretching mode and that the NO2 group undergoes ultrafast structural deformation with a relaxation time of 195 fs. The frequency of the NO2 torsional mode in liquid NM(50.8±0.3 cm^-1) at room temperature is found. Our results prove the structural deformation of two groups in liquid NM molecule occur simultaneously in the intense laser field. 展开更多
关键词 coherent anti-Stokes Raman spectroscopy(CARS) spectra structural deformation intense laser field liquid nitromethane
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Theoretical study on non-sequential double ionization of carbon disulfide with different bond lengths in linearly polarizedlaser fields
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作者 Kai-Li Song Wei-Wei Yu +4 位作者 Shuai Ben Tong-Tong Xu Hong-Dan Zhang Pei-Ying Guo Jing Guo 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期176-182,共7页
By using a two-dimensional Monte-Carlo classical ensemble method, we investigate the double ionization(DI) process of the CS_2 molecule with different bond lengths in an 800-nm intense laser field. The double ioniza... By using a two-dimensional Monte-Carlo classical ensemble method, we investigate the double ionization(DI) process of the CS_2 molecule with different bond lengths in an 800-nm intense laser field. The double ionization probability presents a "knee" structure with equilibrium internuclear distance R = 2.9245 a.u.(a.u. is short for atomic unit). As the bond length of CS increases, the DI probability is enhanced and the "knee" structure becomes less obvious. In addition,the momentum distribution of double ionized electrons is also investigated, which shows the momentum mostly distributed in the first and third quadrants with equilibrium internuclear distance R = 2.9245 a.u. As the bond length of CS increases,the electron momentum becomes evenly distributed in the four quadrants. Furthermore, the energy distributions and the corresponding trajectories of the double-ionized electrons versus time are also demonstrated, which show that the bond length of CS in the CS_2 molecule plays a key role in the DI process. 展开更多
关键词 intense laser field non-sequential double ionization classical ensemble method the bond length
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The momentum distributions of triatomic molecular ion H_(3)^(2+) by intense laser pulses
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作者 Zhi-Xian Lei Shu-Juan Yan +3 位作者 Xin-Yu Hao Pan Ma Sheng-Peng Zhou Jing Guo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2023年第6期112-119,共8页
We investigate theoretically the photoionization of triatomic molecular ion H_(3)^(2+) by numerically solving the two-dimensional time-dependent Schrödinger equations under Bohn-Oppenheimer approximation.The resu... We investigate theoretically the photoionization of triatomic molecular ion H_(3)^(2+) by numerically solving the two-dimensional time-dependent Schrödinger equations under Bohn-Oppenheimer approximation.The results show that the photoelectron momentum distributions(PMDs)of H_(3)^(2+) with different initial states are strongly dependent on the laser ellipticities and molecular orbital symmetry,and the PMDs of degenerate electronic states E^(±)are mirror images.Also,for degenerate electronic states E^(±),vortex structures appear in the PMDs by the counter-rotating circularly polarized laser pulses as the time delay between the two pulses increases,which can be explained by multicenter ionization and ultrafast photoionization model. 展开更多
关键词 momentum distribution ringlike molecules intense laser fields
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Phase-coherence dynamics of frequency-comb emission via high-order harmonic generation in few-cycle pulse trains
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作者 梁畅通 张晶晶 李鹏程 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期205-211,共7页
Frequency-comb emission via high-order harmonic generation(HHG)provides an alternative method for the coherent vacuum ultraviolet(VUV)and extreme ultraviolet(XUV)radiation at ultrahigh repetition rates.In particular,t... Frequency-comb emission via high-order harmonic generation(HHG)provides an alternative method for the coherent vacuum ultraviolet(VUV)and extreme ultraviolet(XUV)radiation at ultrahigh repetition rates.In particular,the temporal and spectral features of the HHG were shown to carry profound insight into frequency-comb emission dynamics.Here we present an ab initio investigation of the temporal and spectral coherence of the frequency comb emitted in HHG of He atom driven by few-cycle pulse trains.We find that the emission of frequency combs features a destructive and constructive coherences caused by the phase interference of HHG,leading to suppression and enhancement of frequency-comb emission.The results reveal intriguing and substantially different nonlinear optical response behaviors for frequency-comb emission via HHG.The dynamical origin of frequency-comb emission is clarified by analyzing the phase coherence in HHG processes in detail.Our results provide fresh insight into the experimental realization of selective enhancement of frequency comb in the VUV–XUV regimes. 展开更多
关键词 high-order harmonic generation frequency comb time-dependent Schro¨dinger equation intense laser field systems
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Review:Coincidence Momentum Imaging:Principle and Application in Molecular Reaction Dynamics 被引量:1
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作者 Li Zhang Huailiang Xu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2018年第4期1-14,共14页
Coincidence Momentum Imaging(CMI) is a powerful imaging technique that can determine the full momentum vectors of all particles released from a single parent molecule in coincidence and thus provide detailed informati... Coincidence Momentum Imaging(CMI) is a powerful imaging technique that can determine the full momentum vectors of all particles released from a single parent molecule in coincidence and thus provide detailed information on transient molecular structures.So far,the CMI technique has been extensively employed for investigating a variety of molecular reaction dynamics induced,e.g.,by particle collisions,intense laser fields and synchrotron radiation.In this article,we first introduce the principle of the CMI technique,which is followed by several typical experimental designs of the CMI systems realizing the coincidence momentum detections.We then present representative examples of studying molecular reaction dynamics using the CMI technique. 展开更多
关键词 Coincidence momentum imaging intense laser fields Molecular reaction dynamics
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Chirping-dependent ionization and dissociation of methane in an intense femtosecond laser field
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作者 任海振 吴成印 +3 位作者 马日 杨宏 蒋红兵 龚旗煌 《Chinese Optics Letters》 SCIE EI CAS CSCD 2003年第1期60-62,共3页
We studied the ionization and dissociation of polyatomic molecule methane in an intense femtosecond laser field with wavelength of 810 nm and intensities ranging from 1.4 × 1014 to 2.6× 1015 W/cm2 by mass sp... We studied the ionization and dissociation of polyatomic molecule methane in an intense femtosecond laser field with wavelength of 810 nm and intensities ranging from 1.4 × 1014 to 2.6× 1015 W/cm2 by mass spectroscopy. Abundant fragment ions were observed in addition to the strong parent ion. The effect of frequency chirp was investigated and it was found that the negatively chirped pulses dramatically enhanced the dissociation probability, which might, be used to control the dissociation pathways. 展开更多
关键词 of as for is Chirping-dependent ionization and dissociation of methane in an intense femtosecond laser field that PES in
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Ionization and Dissociation of Nitrosyl Chloride Molecule in the Intense Femtosecond Laser Field
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作者 姚立 葛茂发 +3 位作者 王殿勋 吴成印 徐楠 龚旗煌 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2006年第7期867-871,共5页
Ionization and dissociation of nitrosyl chloride CINO were studied using femtosecond laser mass spectra technique. Strong fragmental ions NO^+ and Cl^+ were observed with the laser intensity varied from 3.2× 10... Ionization and dissociation of nitrosyl chloride CINO were studied using femtosecond laser mass spectra technique. Strong fragmental ions NO^+ and Cl^+ were observed with the laser intensity varied from 3.2× 10^14 to 2.5×10^15 W/cm^2. These fragmental ions were attributed to the direct dissociation of the parent ions. Electronic structure calculations were also carried out with Hartree-Fock, density functional and correlated levels of theory to understand the possible fragmentation pathways. The very low N-Cl bond energy in the parent ion of nitrosyl chloride is a clear reason for the absence of CINO^+ and CIN^+ ion peaks from the femtosecond laser mass spectrum. 展开更多
关键词 nitrosyl chloride intense femtosecond laser field electronic structure calculation IONIZATION DISSOCIATION
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Single Ultrashort Attosecond Pulse Generation via Combination of Chirped Fundamental Laser and an Ultraviolet Controlling Pulse
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作者 李鹏程 周效信 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第3期445-451,共7页
We theoretically study the high-order harmonic generation (HHG) from a hydrogen atom in an intense few-cycle chirped fundamental laser in combination with an ultraviolet (uv) controlling pulse. The high-order harm... We theoretically study the high-order harmonic generation (HHG) from a hydrogen atom in an intense few-cycle chirped fundamental laser in combination with an ultraviolet (uv) controlling pulse. The high-order harmonic spectrum is calculated by solving the time-dependent Schr6dinger equation using the split-operator method. In our calculation, we present the difference of the high-order harmonic spectrum from one-dimensional (1D) model hydrogen atom and three-dimensional (3D) real hydrogen atom. We found that the plateau of the high-order harmonic generation from the 1D ease and 3D case are all extended effectively to Iv -k 35Up due to the presence of the chirped laser pulse and the HHG supercontinuum spectrum is generated by adding an ultraviolet controlling pulse at a proper time, but the efficiency of the HHC for 3D case is more higher at the near cut-off region than the 1D case. Therefore, the generation of the attosecond pulse by synthesizing the harmonics near cut-off region have some slight differences between 1D and 3D simulations. As a real 3D case study, we show that an isolated 18 as pulse with a bandwidth of 232.5 eV is generated directly by optmizing the combination laser fields. 展开更多
关键词 high-order harmonic generation attosecond pulse generation intense laser field
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