共查询到20条相似文献,搜索用时 15 毫秒
1.
ZENGGao-Jian 《理论物理通讯》2001,35(1):83-86
We study behavior of an atomic wave packet in a circularly polarized electromagnetic wave,and particularly calculate the atomic inversion of the wave packet.A general method of calculation is presented.The results are interesting.For example,if the wave packet is very narrow or /and the interaction is very strong,no matter the atom is initially in its ground state or excited state,the atomic inversion approaches zero as time approaches infinity.If the atom is initially in its ground state and excited state with the probability 1/2 respectively,and if the momentum density is an even function,then the atomic inversion equals zero at any time. 相似文献
2.
The modifications in the time-averaged plasma particle distribution functions in the presence of a large amplitude electromagnetic wave are studied. It is shown that the ponderomotive force is responsible for tail formation, non-zero particle currents and heat fluxes. Explicit results, which describe those effects, are derived. 相似文献
3.
《中国物理快报》2016,(4)
We theoretically study the spin transport through a two-terminal quantum dot device under the influence of a symmetric spin bias and circularly polarized light.It is found that the combination of the circularly polarized light and the applied spin bias can result in a net charge current.The resultant charge current is large enough to be measured when properly choosing the system parameters.The resultant charge current can be used to deduce the spin bias due to the fact that there exists a simple linear relation between them.When the external circuit is open,a charge bias instead of a charge current can be induced,which is also measurable by present technologies.These findings indicate a new approach to detect the spin bias by using circularly polarized light. 相似文献
4.
The particle motion in a standing left circularly polarized wave is studied. For wave frequency lower than the ion cyclotron frequency ?ci, the slow varying trajectory is given by the ponderomotive force FNL=q2?|E|2/[m?(?-?ci)]. However, for ? close to ?ci, stochastic trajectories occur. These stochastic trajectories are due to the overlapping of closed orbits due to each of the propagating waves which form the standing wave. 相似文献
5.
We calculate nonperturbatively the irfluence of a strong circularly polarized laser beam on the hydrogen atom energy levels by making use of the time-independent formalism proposed by one of us. The photoionization cross section of the hydrogen atom irradiated by this laser beam and the angular distribution of photoelectrons are also calculated. From the numerical results we clearly see the intensity dependence of the whole photoionization process,including the intensity dependence of the photoelectron energies. 相似文献
6.
ZHANG Deng ZHANG Qi-Ren 《理论物理通讯》2001,(12)
We calculate nonperturbatively the irfluence of a strong circularly polarized laser beam on the hydrogen atom energy levels by making use of the time-independent formalism proposed by one of us. The photoionization cross section of the hydrogen atom irradiated by this laser beam and the angular distribution of photoelectrons are also calculated. From the numerical results we clearly see the intensity dependence of the whole photoionization process,including the intensity dependence of the photoelectron energies. 相似文献
7.
文章证明:对圆极化光中的∑-原子,存在着由它其中的两个态构造的一个特殊的相干叠加态,当原子最初处于这个态时,它以后将总是几乎处于这个态,而原子处于其他态的概率接近于0。 相似文献
8.
Applying time-independent non-perturbative formalism to the
photo-ionization of hydrogen atom immersed in a strong circularly
polarized standing electromagnetic wave, we calculate the shift of
energy levels and the distortion of wave functions for the
hydrogen atom, the ionization cross section induced by the
standing wave, and the angular distribution of photoelectrons and
obtain some interesting results. 相似文献
9.
This paper presents an investigation of the nonlinear interaction of a high-power right-handed circularly polarized Gaussian electromagnetic beam with an electron-plasma wave in a hot collisionless magnetoplasma. Because of the nonuniform intensity distribution of the electromagnetic beam, in a plane transverse to the direction of propagation, the ponderomotive force becomes finite and leads to the modification in the background carrier density. This leads to the nonlinear coupling between the electromagnetic beam and the electron-plasma wave. Consequently, the focusing of the electron-plasma wave may take place, leading to the enhancement in its amplitude. The excited electron-plasma wave may again interact with the electromagnetic beam and generate an ion-acoustic wave of appreciable power. The power of the generated ion-acoustic wave increases as we approach the critical density region. 相似文献
10.
在对圆极化光调谐及一些近似处理的基础上,圆极化光场中阻尼V-型三能级原子分为6个能级,并针对强场的弱场两种情形,导出了原子能级与能级衰减系数的具体表达式。 相似文献
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12.
报道了利用行波场的共振辐射压力获得准单一速度原子束的实验研究结果,并进行了理论分析。实验上利用斜入射失谐为-100MHz行波光场共振作用原子束可使准单一速度原子束偏转1.7mm,速度宽度小于58m/s。 相似文献
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14.
《中国物理快报》2016,(2)
We present a surface current method to model the graphene rectangular nanoantenna scattering in the terahertz band with Comsol.Compared with the equivalent thin slab method,the results obtained by the surface current method are more accurate and efficient.Then the electromagnetic scattering of circularly polarized terahertz waves on graphene nanoantennas is numerically analyzed by utilizing the surface current method.The dependences of the antenna resonant frequency with the circularly polarized wave on width and length are consistent with those for the linear polarized waves.These results are proved to be useful to design efficient nanoantennas in terahertz wireless communications. 相似文献
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We investigate the features of the spontaneous emission spectra in a cold five-level atomic system coupled by a single elliptically polarized control field. We use wave function approach to derive the explicit and analytical expressions of atomic spontaneous emission spectra. It is shown that some interesting phenomena such as spectralline enhancement, spectral-line suppression, spectral-line narrowing, spectral-line splitting and dark fluorescence can be observed in the spectra by appropriately modulating the phase difference between the right-hand circularly (LHC) and left-hand circularly (RHC) polarized components of the elliptically polarized control field and the intensity of external magnetic field. The number of emission peaks, the positions of fluorescence-quenching points can be also controlled. Furthermore, we propose an ultracold 87Rb atomic system for experimental observation. These investigations may find applications in high-precision spectroscopy. 相似文献
18.
JETP Letters - The temperature dependence of stimulated laser radiation with a high degree of circular polarization in chiral semiconductor nanostructures has been investigated in the temperature... 相似文献
19.
ZHANG Qiren 《理论物理通讯》1997,28(3):355-358
The intensity dependence of the energy and the angular distribution for photoelectrons ejected by a circularly polarized laser beam is derived. The energy shift is similar to that of a combined Zeeman-Stark effect in magnetic and electric fields perpendicular to each other. 相似文献
20.
The dispersion relation of circularly polarized waves in a cold streaming plasma is derived and is shown to be consistent with Lorentz tansforming the stationary plasma dispersion. The waves in the lab frame have modes near n = c/Vs due to the Doppler effect and therefore are relevant in sateliite wave measurements. 相似文献