Transition probabilities of neon atom in a constant electric field

The probability of 5s-3d, 5s-3p, 5p-3s, 5d-3s, 4d-3p, and 4f-3p transitions of Ne I in an electric field is calculated. It is shown that the probability of the permitted transitions 5s-3p and 5p-3s is unchanged with increase in the field from 0 to 50 kV/cm, while the probability of the forbidden transitions 5s-3d and 5d-3s is very small. In the given range of field strengths, the probability of permitted 4d-3p transitions markedly falls and intense forbidden 4f-3p transitions appear. Of the configurations considered, the electric field has most effect on those with2.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 67–70, March, 1979.     

Amplitude-distortion factors for the inelastic scattering of an electron at a neon atom in an electric field

Inelastic electron scattering at a neon atom in the presence of an external electric field is considered. The distortion factors of the cross section _M (F) are calculated for a series of 4d and 5d levels. It is shown that the distortion factor in strong fields is a nonlinear and nonmonotonic function of the field. The distortion factors and transition probabilitiesA , are compared. The correlation between the behavior ofA , and _M (F) is explained by the dependence of the mean dipole moment of the Stark state on the field strength.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 97–110, January, 1996.     

Light-induced drift of neon under optical excitation from a metastable state

A running light wave, resonant with the neon transition 1s₅-2p₂, has been found out to affect the spatial distribution of neon atoms in a positive discharge column. The effect has shown an antisymmetric dependence (typical of the light-induced drift) on the tuning out of the radiation frequency relatively the absorption line centre, as well as on the direction of the light wave vector.     

Free-swarm method: a new approach for measuring electron drift velocity in a gas in an electric field

Summary A new method is presented for measuring electron drift velocityW in a gas in a constant and homogeneous electric field. The technique does not require any correction for electrode and diffusion effects and can give ?instantaneous? values ofW (that is, values measured in a time interval that is limited with respect to the total drift time). We have tested this methodvs. standard methods with good results; it may be useful in the presence of non-stationary behaviour ofW.     

The electron effective mass under strong electric field

The electron effective mass dependence on the high static electric field has been found. The dependence is determined by the field effect on the scattering processes of electrons. The mechanism of “impurity” self-induced transparence of conductors is considered for the case of intense high-frequency electric field.     

Fowler-Nordheim electron tunneling under very intense electric field

In the context of the Fowler-Nordheim tunneling under an electric field of very high strength, electron velocity and drift mobility are calculated as functions of the above strength. In addition, carrier relaxation time is determined.     

Donor electron in a quantum well under the influence of an electric field

The ionization energies and the polarizabilities of a donor in an isolated well of a quasi two dimensional (Q2D) GaAs/Ga_1−x Al _x As heterostructure have been obtained for different well widths including electron-lattice coupling. A wave function that properly reduces to the hydrogenic function in the limiting case has been used. For fields of the order of 10⁵ V/m, the ionization energies decrease slightly with electric fields for all well widths (10 nm to 50 nm) studied. Also for a given electric field, as the well width increases, the ionization energy decreases. For fields of the order of 10⁷ V/m and for smaller well widths (<10 nm), the ionization energy generally increases with electric field. The results also show that for electric fields of this order, no donor bound state associated with the lowest subband is possible for well widths greater than 20 nm. The polarizabilities estimated using the expression for the dipole operator show that as the well width increases, the polarizability values also increase and do not show any abnormal behaviour.     

Coalescence behaviour of two large water-drops in viscous oil under a DC electric field

Electrically driven coalescence is one of the important methods to separate water from crude oils. In this paper, the coalescence behaviour of two water drops was studied experimentally using a high-speed imaging. The results show that the electric force induces the drops migrating towards each other before their contact. However the electric force drags the drops to separate after contact. There is a critical electric field strength above which the two drops would be separated again after they have been coalesced together. The understanding of the electric coalescence could be helpful to advance the design of the electrocoalescencers.     

Self-focusing in photorefractive BaTiO3 crystal under external DC electric field

Experimental observations of 1D and 2D self-focusing in a BaTiO3 crystal under externally DC applied electric field are reported. Stationary self-focusing behaviour can be obtained with and without additional uniform illumination.     

Reversal current observed in micro-and submicro-channel flow under non-continuous DC electric field

In practical applications of biochips and bio-sensors, electrokinetic mechanisms are commonly employed to manipulate and analyze the characteristics of single bio-molecules. To accurately and flexibly control the movement of single molecule within micro-/submicro-fluidic channels, the characteristics of current signals at the initial stage of the flow are systematically studied based on a three-electrode system. The current response of micro-/submicro-fluidic channels filled with different electrolyte solutions in non-continuous external electric field are investigated. It is found, there always exists a current reversal phenomenon, which is an inherent property of the current signals in micro/submicro-fluidics Each solution has an individual critical voltage under which the steady current value is equal to zero The interaction between the steady current and external applied voltage follows an exponential function. All these results can be attributed to the overpotentials of the electric double layer on the electrodes. These results are helpful for the design and fabrication of functional micro/nano-scale fluidic sensors and biochips.     

直流电场下水中石墨烯定向行为研究

纳米颗粒在液体环境中的定向控制与系统物理性能的调控及新型纳米器件的制备等应用领域密切相关.本文使用分子动力学模拟方法,研究了水中单片不带电矩形石墨烯在直流电场下的定向行为.结果发现石墨烯平面趋向平行于电场方向且随着电场强度增大定向性增强,其主要原因在于极性水分子在电场下的响应以及水合作用;减小石墨烯长宽比,石墨烯法向矢量和长边矢量的定向性减弱,定量结果表明法向和长边定向度分别与绕长边和法向的转动扩散系数存在负相关关系.     

Holtzmark electric field distribution in a two-dimensional electron fluid

The Holtzmark distribution for the thermal electric field at a neutral point in a two-dimensional and uncorrelated electron fluid is given by $\text{β(1 + β}{}^2\text{)}{}^{\mathrm{<mtext>?3</mtext><mtext>2</mtext>}}$, with $\text{β =}\text{E}\text{E}{}_0$, and E₀ = πnZ_pe in terms of the density n and perturber Z_pe.     

Dynamics of a pair of electron and hole in semiconductor superlattice under an intense electric field

This paper investigates the behavior of a pair of electron and hole in semiconductor superlattice under an external electric field with the consideration of Coulomb interaction. By numerically calculating the corresponding probability in the nearest neighbor tight binding approximation, we find that the single electron (or the hole) can not be dynamically localized due to the Coulomb interaction, while the dynamic localization of exciton (the pair of the electron and hole) still exists. Moreover we find that with the increase of the intensity of electric field, the exciton can be dynamically localized more completely.     

Effective response in nonlinear spherical coated composites under external AC and DC electric field

By using the perturbation method, effective nonlinear direct current (DC) and alternating current (AC) responses of nonlinear composites with spherical coated inclusions randomly embedded in a host medium are studied under the action of external electric field E_a =E₀ +E₁ sin ωt+E₃ sin 3ωt with different amplitudes and frequencies. The local potentials of composites at all harmonics are given in the inclusion particles and the host regions. All effective nonlinear responses to composites and the relationship between the effective nonlinear responses at all harmonics are also deduced for the spherical coated inclusions in a dilute limit.     

Ultrahot electron formation under excess electron drift through solid Xe

The formation of "hot" (8 eV) electrons under excess electron drift in a moderate electrostatic field through solid xenon has been experimentally proved by observation of secondary electrons emitted from the photocathode. At T=77 K and U=1000 V one drifting electron produces about 20 (172 nm) photons, the efficiency of electric field-to-vacuum ultraviolet emission conversion is 15% tending to grow with temperature. A self-sustained electric discharge has been generated in solid Xe using a three-electrode cell with a zinc cathode.     

Quasi-two-dimensional electron gas in a non-quantizing magnetic field and strong non-quantizing electric field

A calculation is performed to determine the transverse electric field E_y formed in quasi-two-dimensional superlattices in a strong drift field E_x and a weak magnetic field that is perpendicular to the plane of the superlattice (H‖OZ). When the electronic energy spectrum is nonadditive, the field E_y includes both the Hall factor and a spontaneous transverse electric field that exists whetherH is present or not. The situation when the specimen is in a closed circuit with a resistor on the OY axis is examined. As the function E_x, the field E_y is multivalued (multistable) and variable. The stability of the branches of the function E_y(E_x) is determined using a specially introduced (kinetic) “potential” whose minimum corresponds to the steady state of a nonequilibrium electron gas. Volgograd State Pedagogical University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 46–51, July, 1996.     

Radiation of an electron in an electric field

By the methods of classical theory, the motion of an electron in the field of a longitudinal electric wave is analyzed. This field may be taken as a model of the accelerating field at the axis of a linear accelerator. It was shown that the radiation of electrons in this field is analogous to the radiation in a constant homogeneous electric field.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 96–99, May, 1976.The authors are sincerely grateful to Prof. V. A. Bagrov for formulating the problem and for his constant interest in the work.