A Modelling of Tunnelling Current through a Trapezoidal Potential Barrier by Using Exponential Wavefunction Approach

A tunnelling current through a trapezoidal barrier potential has been modelled. The transmittance is determined using the exponential wavefunction approach method. Furthermore, the transmittance is used to calculate the tunnelling current density by applying the Gauss-Laguerre quadrature method. The simulation results show the increasing bias voltage causes the raising tunnelling current, and an increase of temperature is proportional to the tunnelling current.

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A LEED Fine Structure Study of Oxygen Adsorption on Cu(001) and Cu(111)

Australian Journal of Physics ◽

10.1071/ph900519 ◽

1990 ◽

Vol 43 (5) ◽

pp. 519 ◽

Cited By ~ 20

Author(s):

C Hitchen ◽

S Thurgate ◽

P Jennings

Keyword(s):

Fine Structure ◽

Long Range ◽

Potential Barrier ◽

Incident Beam ◽

Oxygen Adsorption ◽

Structure Study ◽

Threshold Effects ◽

Range Image ◽

Adsorption Sites ◽

Barrier Potential

LEED fine structure features are due to an interference between the measured beam (usually the specular) and a pre-emergent beam. This pre-emergent beam is internally reflected at the surface potential barrier and is subsequently diffracted by the substrate into the same direction as the beam under observation. As a result of the long-range image nature of the barrier potential, a rydberg-like series of peaks, converging on the emergence energy of the pre-emergent beam, is produced. Fine structure features, or threshold effects, occur at very low incident beam energies (typically <40 eV) and are extremely sensitive to the surface order of the crystal. The changes that occur to the fine structure features when atoms are adsorbed onto the surface contain information regarding the nature of the chemisorption process. In some cases it is possible to infer adsorption sites. In this work measurements are made of the fine structure features for the (001) and (111) surfaces of copper as a function of oxygen exposure. Analysis of these data shows that oxygen adsorption on (u(111) takes place in a disordered manner and results in a roughening of the surface, while for (u(OOl) the adsorption produces an ordered overlayer with oxygen atoms in the 2-fold bridge sites.

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Formation of embedded Co nanostructures in Cu(001) surface under electromigration

Modern Physics Letters B ◽

10.1142/s0217984921500901 ◽

2020 ◽

pp. 2150090

Author(s):

S. V. Kolesnikov ◽

A. L. Klavsyuk ◽

A. M. Saletsky

Keyword(s):

Monte Carlo ◽

Current Density ◽

Kinetic Monte Carlo ◽

The Self ◽

Atomic Scale ◽

Self Organization ◽

Simulation Results ◽

Self Learning

Formation of embedded Co nanostructures in Cu(001) surface under electromigration is investigated on the atomic scale by performing self-learning kinetic Monte Carlo (kMC) simulations. The analysis of simulation results reveals the following important result. The electromigration of vacancies does not influence on the self-organization of Co nanostructures in the first layer of Cu(001) surface at all values of current density, which can be achieved in experiments.

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Electron Spin-Dependent Tunneling Current through a Trapezoidal Potential Barrier under Airy Wavefunction Approach

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.833.152 ◽

2020 ◽

Vol 833 ◽

pp. 152-156

Author(s):

Fatimah A. Noor ◽

Ezra Nabila ◽

Euis Sustini ◽

Khairurrijal

Keyword(s):

Potential Barrier ◽

Bias Voltage ◽

Electron Spin ◽

Tunneling Current ◽

Spin States ◽

Analytical Expression ◽

Zinc Blende ◽

Spin Polarized

In this paper, an analytical expression of the electron spin-dependent tunneling current through a potential barrier by applying a bias voltage was investigated. An Airy wavefunction was applied to derive the transmittance through the barrier by considering a zinc-blende material, which depends on the spin states indicated as ‘up’ and ‘down’. The obtained transmittance was employed to compute the polarization and spin-dependent tunneling current. The spin-dependent tunneling current was then observed at various bias voltages and temperatures. It was shown that the spin-polarized current increases as the bias voltage increases. It was also shown that the increase of temperature enhances the spin-dependent tunneling current.

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Electrostatic and Electrodynamic Field Analyses of 33kV Line Insulators

International Journal of Emerging Electric Power Systems ◽

10.2202/1553-779x.1330 ◽

2006 ◽

Vol 7 (3) ◽

Author(s):

Ibrahim A. Metwally ◽

Md Abdus Salam ◽

Ali Al-Maqrashi ◽

Saif AR Sumry ◽

Saif SH Al-Harthy

Keyword(s):

Electric Field ◽

Current Density ◽

High Current Density ◽

Experimental Tests ◽

Finite Element Models ◽

High Current ◽

Density Profiles ◽

Fully Integrated ◽

Software Modules ◽

Simulation Results

Electrostatic and electrodynamic field analyses of 33kV line insulators were introduced to compare the electric-field and the current density profiles of commonly used line insulators in Oman; namely, silicone rubber (SiR) and porcelain line post insulators, and porcelain cap and pin insulator string. SLIM software package was used for such simulation, which is a fully integrated collection of software modules that provides facilities for the generation and solution of electromagnetic finite element models. The simulation results reveal that for the electrostatic simulation under pollution conditions, SiR and porcelain line-post insulators give maximum values of the electric field of 360kV/m and 1700kV/m, respectively. The latter value exceeds the recommended electric field level of 500kV/m. For the electrodynamic simulation under pollution conditions, the electric field and the current density are much higher for porcelain insulator compared to those of SiR insulator. The simulation of four cap-pin standard insulator string reveals that there is high electric field (1250kV/m) at the cap-insulator gap which can cause high current density for polluted case. Finally, the trend of the simulation results has been verified by experimental tests, which has been conducted on different 33kV line insulators having different designs and materials.

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Effect of applied bias voltage on grain boundary potential barrier height (Φ b ) in semiconductor nanocrystals

Electronic Materials Letters ◽

10.1007/s13391-012-2129-4 ◽

2013 ◽

Vol 9 (2) ◽

pp. 227-230 ◽

Cited By ~ 2

Author(s):

T. Prakash ◽

S. Ramasamy

Keyword(s):

Grain Boundary ◽

Barrier Height ◽

Potential Barrier ◽

Bias Voltage ◽

Semiconductor Nanocrystals ◽

Potential Barrier Height ◽

Applied Bias ◽

Applied Bias Voltage ◽

Boundary Potential

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Designing and Analysis of Lightweight InGaN/GaN PV Cell

International Journal of Recent Contributions from Engineering Science & IT (iJES) ◽

10.3991/ijes.v8i2.14809 ◽

2020 ◽

Vol 8 (2) ◽

pp. 46

Author(s):

Shadia Chowdhury ◽

Md. Moidul Islam ◽

Md. Mostafizur Rahman ◽

Mission Kumar Debnath ◽

Samera Hossain

Keyword(s):

Solar Cell ◽

Electric Field ◽

Power Conversion Efficiency ◽

Current Density ◽

Electric Potential ◽

Power Conversion ◽

Type Layer ◽

Pv Cell ◽

Back Reflector ◽

Simulation Results

<p class="0abstract">This paper is an effort to analyze the performance and also increase the efficiency of InGaN/GaN solar cell. InGaN/GaN solar cell contains p and n-type layer of GaN and intrinsic layer of InGaN. The proposed structure of solar cell also contains front TCO, back TCO and back reflector. Performance of the designed solar cell was checked based on electric field, current density and electric potential generated in the designed cell. J-V curve is the most important factor to analyze the performance of the solar cell. Power conversion efficiency and fill factors have been calculated from this graph. According to the analysis of the simulation results efficiency of the designed solar cell was 12.91%. At the end, this thesis is about designing successfully with an efficient InGaN/GaN solar cell for further use in solar applications.</p>

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Determination of a High Potential Barrier Hindering Internal Rotation from the Analysis of the Ground State Spectrum: The Case of Ethyl Cyanide

Zeitschrift für Naturforschung A ◽

10.1515/zna-1980-1102 ◽

1980 ◽

Vol 35 (11) ◽

pp. 1136-1141 ◽

Cited By ~ 2

Author(s):

D. Boucher ◽

A. Dubrulle ◽

J. Demaison ◽

H. Dreizler

Keyword(s):

Internal Rotation ◽

Potential Barrier ◽

Ground State ◽

High Potential ◽

State Transitions ◽

Rotational Spectrum ◽

Barrier Potential ◽

High Potential Barrier

Abstract The ground state rotational spectrum of ethyl cyanide has been reinvestigated between 8 and 250 GHz. The barrier potential V3 is calculated from 11 high J, ground state transitions which were found split into doublets. V3 is 3007 cal/mole, assuming Iα = 3.167 u Å2 and ∢ (i,a) = 48.65°. The splittings of the K-doublet transitious have also been analyzed.

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