Showing papers on "Electric potential published in 1984"
TL;DR: In this article, the authors describe a novel charge tranport scheme in semiconductors, in which the field responsible for the charge transport is independent of the depletion field, which leads to the following new semiconductor detectors: (1) Semiconductor Draft Chamber; (2) Ultra low capacitance - large semiconductor x-ray spectrometers and photodiodes; and (3) Fully depleted thick CCD.
699 citations
TL;DR: Only unbiased results of evoked potential data evaluation can be hoped to elucidate or map successfully into information processing models established by other methods, e.g. behavior measurements.
346 citations
TL;DR: In this paper, the adiabatic energy gain of electrons in the stationary electric and magnetic field structure of collisionless shock waves was examined analytically in reference to conditions of the earth's bow shock.
Abstract: The adiabatic energy gain of electrons in the stationary electric and magnetic field structure of collisionless shock waves was examined analytically in reference to conditions of the earth's bow shock. The study was performed to characterize the behavior of electrons interacting with the cross-shock potential. A normal incidence frame (NIF) was adopted in order to calculate the reversible energy change across a time stationary shock, and comparisons were made with predictions made by the de Hoffman-Teller (HT) model (1950). The electron energy gain, about 20-50 eV, is demonstrated to be consistent with a 200-500 eV potential jump in the bow shock quasi-perpendicular geometry. The electrons lose energy working against the solar wind motional electric field. The reversible energy process is close to that modeled by HT, which predicts that the motional electric field vanishes and the electron energy gain from the electric potential is equated to the ion energy loss to the potential.
228 citations
TL;DR: In this paper, the subband structure and charge distribution in an AlxGa1−xAs/GaAs heterojunction as a function of gate voltage at room temperature has been performed.
Abstract: A calculation of the subband structure and charge distribution in an AlxGa1−xAs/GaAs heterojunction as a function of gate voltage at room temperature has been performed. The results show that usually about 80% of the electrons in the channel are in the lowest two subbands and describe for the first time quantitatively the transition from the simple capacitive charge control regime to the regime where the channel density is no longer controlled by the gate voltage.
139 citations
TL;DR: It is proposed that the time course of the electric field-induced membrane breakdown can be divided into three stages: (i) growth of the membrane surface fluctuations, (ii) molecular rearrangements leading to membrane discontinuities, and (iii) expansion of the pores, resulting in the mechanical breakdown of the membranes.
Abstract: A simple viscoelastic film model is presented, which predicts a breakdown electric potential having a dependence on the electric pulse length which approximates the available experimental data for the electric breakdown of lipid bilayers and cell membranes (summarized in the reviews of U. Zimmermann and J. Vienken, 1982, J. Membrane Biol. 67:165 and U. Zimmermann, 1982, Biochim. Biophys. Acta 694:227). The basic result is a formula for the time tau of membrane breakdown (up to the formation of pores): tau = alpha (mu/G)/(epsilon 2m epsilon 2oU4/24 sigma Gh3 + T2/sigma Gh-1), where alpha is a proportionality coefficient approximately equal to ln(h/2 zeta o), h being the membrane thickness and zeta o the amplitude of the initial membrane surface shape fluctuation (alpha is usually of the order of unity), mu represents the membrane shear viscosity, G the membranes shear elasticity modules, epsilon m the membrane relative permittivity, epsilon o = 8.85 X 10(-12) F/m, U the electric potential across the membrane, sigma the membrane surface tension and T the membrane tension. This formula predicts a critical potential Uc; Uc = (24 sigma Gh3/epsilon 2m epsilon 2o)1/4 (for tau = infinity and T = 0). It is proposed that the time course of the electric field-induced membrane breakdown can be divided into three stages: (i) growth of the membrane surface fluctuations, (ii) molecular rearrangements leading to membrane discontinuities, and (iii) expansion of the pores, resulting in the mechanical breakdown of the membrane.
135 citations
TL;DR: In this paper, a model of the liquid-metal ion-source shape consisting of a jet-like protrusion on the end of a Taylor cone shape is shown to be consistent with a field evaporation mechanism of ion formation.
Abstract: A model of the liquid-metal ion-source shape consisting of a jet-like protrusion on the end of a Taylor cone shape is shown to be consistent with a field evaporation mechanism of ion formation, fluid dynamic considerations, space charge effects and recent TEM observations. The diameter of the ion emitting area is found to be only a few tens of A. Self-consistent numerical calculations of electric potential and particle trajectories predict emission characteristics which compare favorably with experimental results.
122 citations
TL;DR: In this article, a criterion for oblique alignment, depending on the double-layer parameters and on the external magnetization, is obtained, which predicts that accelerated heavy ions will be substantially less magnetic field aligned than will accelerated hydrogen ions, thus suggesting auroral double layers as a source of high-energy ion conics.
Abstract: Magnetized test ions are subjected to acceleration through a numerically simulated oblique double layer in order to determine whether they emerge with velocity vectors aligned with or oblique to the ambient magnetic field. A criterion for oblique alignment, depending on the double-layer parameters and on the external magnetization, is obtained. When it is applied to observed and theoretical auroral double layers, this criterion predicts that accelerated heavy ions will be substantially less magnetic field aligned than will accelerated hydrogen ions, thus suggesting auroral double layers as a source of high-energy ion conics. Test particle simulations are also used to investigate the perpendicular heating of ions at low altitudes by the electric fields associated with moving auroral arcs. The rapid motion of small-scale structures in the arcs is suggested as a source of low-energy conical ion distributions, and the slow drifts of the entire arc forms are inferred to heat ionospheric ions.
121 citations
TL;DR: From the magnetic and electric field observations on the DE-2 satellite, it was deduced that the perturbation magnetic field and the electric field in the field-aligned current regions are, as a rule, orthogonal to each other and are highly correlated.
Abstract: From the magnetic and electric field observations on the DE-2 satellite it is deduced that the perturbation magnetic field and the electric field in the field-aligned current regions are, as a rule, orthogonal to each other and are highly correlated. This deduction is equivalent to the statement that the Poynting vector calculated from these magnetic and electric field components is equal to the ionospheric energy dissipation and that the height-integrated Hall current is divergence free. The state described is interpreted as a frequently prevailing mode of the magnetosphere-ionosphere coupling involving field-aligned currents.
105 citations
TL;DR: In this paper, it was shown that less than 10 percent of the typical magnetospheric potential resulted from viscous interaction or similar processes, and the authors concluded that the majority of the magnetic fields generated by the ISEE 1 satellite were not caused by viscous interactions or other processes.
Abstract: Dusk-to-dawn electric fields just inside the magnetospause have been suggested to be the products of either a viscous interaction or other processes occurring in a closed magnetosphere. Attention is accordingly given to electric field measurements conducted during 28 crossings of the magnetopause by the ISEE 1 satellite, within 2 hours of local dusk, in 1980. Although dusk-to-dawn fields containing potentials of a few kV were often observed, it is concluded that less than 10 percent of the typical magnetospheric potential resulted from viscous interaction or similar processes.
103 citations
TL;DR: In this paper, the authors investigated the obstruction effect on the microscopic translational motion of water molecules and of the cation (C2H5)4N+ caused by gels.
53 citations
TL;DR: In this article, the effects of electric fields on the front wave propagation in the iodate-arsenous acid reaction system were reported, and the mechanism of the electric field action was discussed.
TL;DR: In this paper, a measurement with field sensors is the only way to determine the electric field strength in such an electrode system, and it is shown that such measurements are unsatisfying for the determ, if predischarges in the arrangement are observed.
Abstract: For the development and optimal design of high voltage apparatus the knowledge of the electric field strength in insulation systems is necessary. Beside field calculation methods, which are in general up to now unsatisfying for the determ, ination of the electric field if predischarges in the arrangement are observed, measurement with field sensors is the only way to determine the electric field strength in such an electrode system.
TL;DR: In this article, a new mechanism of producing auroral electrons was proposed, where field-aligned plasma jets, presumably generated by magnetic reconnection in the magnetotail, give rise to charge separation along the mirror field whereby electrons are accelerated by the parallel electric field.
Abstract: A new mechanism of producing auroral electrons is proposed. Field-aligned plasma jets, presumably generated by magnetic reconnection in the magnetotail, give rise to charge separation along the mirror field whereby electrons are accelerated by the parallel electric field. The analysis shows that the potential difference can be expressed by eΦ=W∥ i (1-1/γ)R/(1+R) where W∥ i is the ion parallel flow energy, γ is the mirror ratio and R is the ratio of the electron to ion temperature. In the magnetotail, W∥ i≃10keV, R≃0.2∽0.5 and γ≃10³, so that the potential drop can reach several kV which is reasonable to make auroral electrons.
TL;DR: Using the inflection point method of interpreting emissive probes, it is shown that it is possible to measure the electric space potential established between two parallel metal plates in a vacuum as mentioned in this paper.
Abstract: Using the inflection point method of interpreting emissive probes, it is shown that it is possible to measure the electric space potential established between two parallel metal plates in a vacuum
TL;DR: In this paper, the exact solutions of the Dirac equation with a linear scalar confining potential in a uniform electric field are given, and it is found that, if the scalar potential is stronger than that of the electric field, confinement is permanent.
Abstract: The exact solutions of the Dirac equation with a linear scalar confining potential in a uniform electric field are given. It is found that, if the scalar potential is stronger than that of the electric field, confinement is permanent. On the contrary, if the electric field is strong enough, confinement is impossible due to the Klein paradox.
TL;DR: A theoretical model for explaining observed data on electric behavior, such as d.c. current-voltage characteristics and self-sustained oscillations of the electric potential, is proposed for an artificial membrane prepared by infiltrating dioleyl phosphate into pores of a Millipore filter.
TL;DR: In this paper, a memory effect due to real-space hot-electron transfer between two conducting GaAs layers separated by a graded AlGaAs barrier is studied, where application of a lateral electric field to one of the layers enhances its electron temperature and leads to a charge injection into the other layer which is kept floating.
Abstract: We studied a memory effect due to the real‐space hot‐electron transfer between two conducting GaAs layers separated by a graded AlGaAs barrier. Application of a lateral electric field to one of the layers enhances its electron temperature and leads to a charge injection into the other layer which is kept floating. As the heating voltage is removed, the injected electrons remain in the second layer, giving rise (at low temperatures, 77 K) to a persistent potential difference. Kinetics of the charge‐up process are studied at different heating voltages.
TL;DR: In this paper, the gauge-invariant approach to the potential via the Wilson loop is generalized, replacing the static sources by the appropriate Dirac currents, and the resulting expression is expanded with respect to l/m2 and then brought into a suitable form.
Abstract: The gauge-invariant approach to the potential via the Wilson loop is generalized, replacing the static sources by the appropriate Dirac currents. The resulting expression is expanded with respect to l/m2 and then brought into a suitable form. For the evaluation the only input we employ is the area law for large distances. This allows us to understand how the electric flux tube picture emerges in the case of moving quarks, and why magnetic terms do not contribute to spin-dependent corrections. The only surviving spin dependence is a spin-orbit term like that from a scalar potential, but with the opposite sign.
Patent•
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12 Mar 1984
TL;DR: An electric current generating cell comprising an open-cellular foamed semiconductor and means to excite the semiconductor to produce electric potential is described in this paper, where the authors describe an electric current generator consisting of an open cell and an open semiconductor.
Abstract: An electric current generating cell comprising an open-cellular foamed semiconductor and means to excite the semiconductor to produce electric potential.
TL;DR: In this article, the flatband voltage and the characteristic energy of the deep localized states in amorphous silicon-based alloy field effect transistors were determined from their currentvoltage characteristics.
Abstract: We propose a new technique to determine both the flat‐band voltage and the characteristic energy of the deep localized states in amorphous silicon‐based alloy field‐effect transistors from their current‐voltage characteristics. We also analyze the effects of surface states and show that they become important when their density is greater than 1011 cm−2 eV−1.
TL;DR: In this article, two-dimensional numerical solutions of the coupled, nonlinear, partial differential equations governing the electric potential, carrier drift, diffusion, generation, and recombination in a finite semiconductor slab in the presence of a magnetic field are presented.
Abstract: We present two-dimensional numerical solutions of the coupled, nonlinear, partial differential equations governing the electric potential, carrier drift, diffusion, generation, and recombination in a finite semiconductor slab in the presence of a magnetic field. This enables device modeling for general geometries, doping levels, and injection conditions, where the effect of the magnetic field cannot be expressed simply in terms of Hall voltage, Lorentz deflection, or magnetoconcentration.
TL;DR: In this article, the time dependence of currents in poling circuits with varying RC time constants has been investigated and a phenomenological description of the poling process is presented which allows one to determine the dependence of polarization with respect to the voltage across the sample, and the corresponding density function shows a steep rise in polarization at about 2400 V (average electric field strength 1 MV/cm) followed by an exponentially decaying tail toward higher voltages.
Abstract: The polarization process which takes place during electric poling of poly(vinylidene fluoride) is investigated by measuring the time dependence of currents in poling circuits with varying RC time constants. For applied voltages between 3 and 8 kV (average field strengths 1.2–3.2 MV/cm) and RC values between 10 and 10−3 s, the current‐time behavior, normalized by the corresponding RC time constants and initial current values, can be described by a single curve (quasi‐steady state). Such a representation indicates that the switching of polarization is simply a voltage‐ or field‐induced effect. A phenomenological description of the poling process is presented which allows one to determine the dependence of polarization with respect to the voltage across the sample. The corresponding density function shows a steep rise in polarization at about 2400 V (average electric field strength 1 MV/cm) followed by an exponentially decaying tail toward higher voltages. Implication of such a distribution is discussed briefly.
TL;DR: In this paper, a quasi-three-dimensional charge-coupled circuit for creating a charge packet equal to the difference of two input charge packets is analyzed, where the signal charges are transferred to the circuit through remote and possibly multiple floating diffusion collectors which may also function as summing nodes.
Abstract: A new charge-coupled circuit for creating a charge packet equal to the difference of two input charge packets is analyzed. The circuit features inherent linearity through the use of quasi-three-dimensional charge-coupling, and can be implemented in a compact way. Depending upon the areal ratio of the circuit's primary electrodes, various fixed gains in the transfer characteristic may be obtained. The signal charges are transferred to the circuit through remote and possibly multiple floating diffusion collectors which may also function as summing nodes. Multiple copies of the output charge packet may be regenerated without refreshing the circuit input. A large geometry prototype device has been fabricated and characterized. The device demonstrates the operation of the circuit and features less than -40-dB linearity distortion over a dynamic range which exceeds 70 dB. Improved performance is expected in smaller geometry devices.
TL;DR: In this paper, the electric potential and field fluctuations in two-dimensional Coulomb systems were investigated and it was shown that the fluctuations of the potential at a point are infinite in the thermodynamic limit.
Abstract: We supplement a previous paper on three-dimensional systems by studying the electric potential and field fluctuations in two-dimensional Coulomb systems. The novelty in two dimensions is that the fluctuations of the potential at a point are infinite in the thermodynamic limit. However, the potential difference between two points has finite fluctuations, which resemble the ones which occur in the three-dimensional case. The field fluctuations are also rather similar in both cases. The correlations do not have a fast decay. Explicit results are obtained for a solvable model; the fluctuations of the potential are Gaussian with an infinite variance.
TL;DR: In this paper, it was shown that the well-known magnetic Aharonov-Bohm effect permits the instantaneous transmission of signals, but its electric counterpart cancels the effect.
Patent•
29 Oct 1984
TL;DR: In this article, the third electrode is maintained at an electric potential equal to half of the electric potential between the two plate electrodes, and the fluid is passed between the plates and the changes in capacitance between the plate electrodes are measured.
Abstract: The apparatus has two plate electrodes surrounded by a third electrode. The third electrode is maintained at an electric potential equal to half of the electric potential between the two plate electrodes. The fluid is passed between the two plate electrodes and the changes in capacitance between the two plate electrodes is measured. From this measurement the fraction of gas in the fluid is determined.