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Momentum Spectroscopy for Multiple Ionization of Cold Rubidium in the Elliptically Polarized Laser Field 下载免费PDF全文
Employing recently developed magneto-optical trap recoil ion momentum spectroscopy(MOTRIMS) combined with cold atoms,strong laser pulse,and ultrafast technologies,we study momentum distributions of the multiply ionized cold rubidium(Rb) induced by the elliptically polarized laser pulses(35 fs,1.3×1015 W/cm2).The complete vector momenta of Rbn+ ions up to charge state n=4 are recorded with extremely high resolution(0.12 a.u.for Rb+).Variations of charac... 相似文献
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ASYMMETRY PARAMETERS AND DIFFERENTIAL CROSS SECTIONS FOR PHOTOIONIZATION-EXCITATION OF HELIUM 下载免费PDF全文
Asymmetry parameter β2 for photoionization of helium leaving the He+ ion in the n=2 level and differential cross sections(DCSs) in the n=2,3,4 levels with photon emission angle θ=900 are provided at photon energies 69-76.8 eV employing the R-matrix method with a 20-term target representation, in which five polarization orbitals \bar{6}l are included. The asymmetry parameter β2 and the DCS, in the n=2 level in the region of 69-73 eV, are in good agreement with available experimental and theoretical results. Above the n=3 threshold, we present new theoretical results along with measurements. No theoretical and experimental results can be used to compare with the present calculations of the DCSs for photoionization into the He+ ion in the n=3,4 levels. 相似文献
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Electron scattering from argon in a laser field is investigated empolying the second-order perturbation theory. The absolute differential cross sections of e-Ar scattering with multiphoton exchange in special scattering geometries G1 (for small-angle scattering) and G2 are calculated. Our results are found to be better than other theoretical results as compared with the experimental data. 相似文献
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ASYMMETRY PARAMETERS AND DIFFERENTIAL CROSSSECTIONS FOR PHOTOIONIZATION-EXCITATION OF HELIUM 下载免费PDF全文
Asymmetry parameterβ2 for photoionization of helium leaving the He+ ion in the n = 2 level and differential cross sections(DCSs) in the n = 2, 3, 4 levels with photon emission angle θ=90°are provided at photon energies 69-76.8 eV employing the R-matrix method with a 20-term target representation, in which five polarization orbitals 6l are included. The asymmetry parameter β2 and the DCS, in the n=2 level in the region of 69-73eV, are in good agreement with available experimental and theoretical results. Above the n = 3 threshold, we present new theoretical results along with measurements. No theoretical and experimental results can be used to compare with the present calculations of the DCSs for photoionization into the He+ ion in the n = 3, 4 levels. 相似文献
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电子被氩,氪,氙原子散射总截面的光学模型研究 总被引:1,自引:0,他引:1
文中基于光学模型势方法,详细分析并改进了一种准自由模型吸收势,把它作为光学模型的虚部,在能量0.1-300eV的范围内计算了电子被Ar,Kr,Xe原子散射的总截面,计算结果与实验值进行了比较。 相似文献
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正,负电子被原子散射的光学势方法—e^±—Na散射总截面的计算 总被引:2,自引:0,他引:2
将原子核散射理论中的光学势方法应用于正、负电子被原子散射的计算,提出了不含任意参数的光学势以及由此确定散射矩阵元的方法,计算了低能(≤50eV)正、负电子被Na散射的总截面并与实验结果进行了比较。 相似文献
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Observation of photon recoil effects in single-beam absorption spectroscopy with an ultracold strontium gas 下载免费PDF全文
We report on observing photon recoil effects in the absorption of a single monochromatic light at 689 nm through an ultracold 88Sr gas,where the recoil frequency is comparable to natural linewidth of the narrow-line transition 5s2 1S0-5s5p 3P1 in strontium.In the regime of high-saturation,the absorption profile becomes asymmetric due to the photon-recoil shift,which is of the same order as the natural linewidth.The lineshape is described by an extension of the optical Bloch equations including the momentum transfers to atoms during emission and absorption of photons.Our work reveals the photon recoil effects in a simplest single-beam absorption setting,which is of significant relevance to other applications such as saturation spectroscopy,Ramsey interferometry,and absorption imaging. 相似文献
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Rabi Oscillations and Coherence Dynamics in Terahertz Streaking-Assisted Photoelectron Spectrum 下载免费PDF全文
We present an approach,a Terahertz streaking-assisted photoelectron spectrum(THz SAPS),to achieve direct observations of ultrafast coherence dynamics with timescales beyond the pulse duration.Using a 24 fs probe pulse,the THz SAPS enables us to well visualize Rabi oscillations of 11.76 fs and quantum beats of 2.62 fs between the 5S1/2 and 5P3/2 in rubidium atoms.The numerical results show that the THz SAPS can simultaneously achieve high resolution in both frequency and time domains without the limitation of Heisenberg uncertainty of the probe pulse.The long probe pulse promises sufficiently high frequency resolution in photoelectron spectroscopy allowing to observe Autler-Townes splittings,whereas the streaking THz field enhances temporal resolution for not only Rabi oscillations but also quantum beats between the ground and excited states.The THz SAPS demonstrates a potential applicability for observation and manipulation of ultrafast coherence processes in frequency and time domains. 相似文献
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利用二阶微扰论的方法计算了动量转移与激光场的偏振方向垂直条件下,电子-He原子碰撞的自由-自由跃迁的单光子和两光子交换的微分截面,结果与最近的实验结果符合得很好。 相似文献