scholarly journals Model of a single-electron transistor based on endohedral fullerene (Sc3N)@C80

2021 ◽  
Vol 2140 (1) ◽  
pp. 012006
Author(s):  
A G Duisenova ◽  
D M Sergeyev
Keyword(s):  
Total Energy ◽  
Bias Voltage ◽  
Gate Voltage ◽  
Density Functional ◽  
Stability Diagram ◽  
Single Electron ◽  
Total Charge ◽  
Single Electron Transistor ◽  
Scandium Nitride ◽  
The Stability

Abstract In this work within the framework of the density functional theory and the method of nonequilibrium Green’s functions the dependences of the total energy of molecules C80-SET and (Sc3N)@C80 - SET on their total charge, the dependence of the total energy from the gate voltage and the stability diagram of the single-electron transistor have been determined. It is noted that for transition to switch to on mode (Sc3N)@C80-SET it is necessary to apply the gate voltage in the range from 0.019 ≤ VG ≤ 5.940 with the bias voltage -2.040 ≤ VSD ≤ 2.155 V. Considering that at values of bias voltage equal to –0.381 ≤ VSD ≤ 0.533 V there is no voltage on the substrate (VG = 0 V) and electric current does not flow. It is shown that the total energy at negative values of charge is higher than at positive charges and that the area of the Coulomb rhombus in fullerene with scandium nitride is 5.3 times larger than in “pure” fullerene.

CHARGE STABILITY AND CONDUCTANCE ANALYSIS OF ANTHRACENE-BASED SINGLE ELECTRON TRANSISTOR

2013 ◽  
Vol 12 (06) ◽  
pp. 1350045 ◽  
Author(s):  
ANURAG SRIVASTAVA ◽  
BODDEPALLI SANTHIBHUSHAN ◽  
PANKAJ DOBWAL
Keyword(s):  
Coulomb Blockade ◽  
Density Functional ◽  
Stability Diagram ◽  
Single Electron ◽  
Single Electron Transistor ◽  
Functional Theory ◽  
Charge Stability ◽  
Anthracene Molecule ◽  
The Stability ◽  
Experimental Values

The present paper discusses the investigation of electronic properties of anthracene-based single electron transistor (SET) operating in coulomb blockade region using Density Functional Theory (DFT) based Atomistix toolkit-Virtual nanolab. The charging energies of anthracene molecule in isolated as well as electrostatic SET environments have been calculated for analyzing the stability of the molecule for different charge states. Study also includes the analysis of SET conductance dependence on source/drain and gate potentials in reference to the charge stability diagram. Our computed charging energies for anthracene in isolated environment are in good agreement with the experimental values and the proposed anthracene SET shows good switching properties in comparison to other acene series SETs.

GRAPHYNE-BASED SINGLE ELECTRON TRANSISTOR: AB INITIO ANALYSIS

NANO ◽  
2014 ◽  
Vol 09 (03) ◽  
pp. 1450032 ◽  
Author(s):  
J. V. N. SARMA ◽  
RAJIB CHOWDHURY ◽  
R. JAYAGANTHAN
Keyword(s):  
Coulomb Blockade ◽  
Density Functional ◽  
Stability Diagram ◽  
Single Electron ◽  
Present System ◽  
Single Electron Transistor ◽  
Poisson Equations ◽  
Charge Stability ◽  
Coulomb Blockade Regime ◽  
Charging Energy

The application of graphyne for a single-electron transistor (SET) that is operating in the Coulomb blockade regime is investigated in the first principles framework. Density functional theory modeling for graphyne has been used and the device environment has been described by a continuum model. The interaction between graphyne and the SET environment is treated with self-consistent Poisson equations. The charging energy as a function of gate voltage thus calculated has been used to obtain the charge stability diagram for the present system. The effect of electrode separation and the position of the molecule with respect to the dielectric on the gate coupling have been studied further. As compared with the previously studied systems on this line, graphyne has been observed to provide the gate coupling that is nearly close to that of benzene and graphene, but significantly greater than fullerene-based systems.

scholarly journals An ab Initio Calculations of Single-Electron Transistor Based Single Walled Carbon Nanotube of Ultra-Small Diameter

2020 ◽  
Keyword(s):  
Carbon Nanotube ◽  
Density Functional ◽  
Energy Levels ◽  
Small Diameter ◽  
Stability Diagram ◽  
Single Electron ◽  
Single Electron Transistor ◽  
Single Walled Carbon Nanotube ◽  
Single Walled Carbon ◽  
Charge Stability

In this paper, we have investigated the charge stability diagram and conductance dependence on source drain bias and gate voltage of carbon nanotube based single electron transistor (SET) by using first principle calculations. All calculations have been executed by using ATK-VNL simulation package based on density functional theory (DFT). We have applied these calculations for carbon nanotube based SET; the nanotube has been placed just above the dielectric ( ) in between the source and drain electrodes of gold. The single walled carbon nanotube has been used in SET, which have ultra-small diameter and (4,0) configuration. The addition energy of the device has been calculated, which can be defined as the difference between the electron affinity, and ionization energies. The calculated values of energies have been found to be -10.17694 eV and -11.04034 eV for isolated phase and SET environment respectively. In electrostatic environment, the results were showing the regularization of molecular energy levels and therefore the addition energy reduced. The calculations for additional energies, variations of total energies to that of the gate voltages and charge stability diagram (CSD) have also been done in this study.

Site preference and atomic ordering in the ternary Rh5Ga2As: first-principles calculations

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Nilanjan Roy ◽  
Sucharita Giri ◽  
Harshit ◽  
Partha P. Jana
Keyword(s):  
Total Energy ◽  
First Principles ◽  
Density Functional ◽  
Structure Type ◽  
Site Preference ◽  
X Ray Diffraction ◽  
Atomic Ordering ◽  
Functional Theory ◽  
The Stability ◽  
Bonding Characteristics

Abstract The site preference and atomic ordering of the ternary Rh5Ga2As have been investigated using first-principles density functional theory (DFT). An interesting atomic ordering of two neighboring elements Ga and As reported in the structure of Rh5Ga2As by X-ray diffraction data only is confirmed by first-principles total-energy calculations. The previously reported experimental model with Ga/As ordering is indeed the most stable in the structure of Rh5Ga2As. The calculation detected that there is an obvious trend concerning the influence of the heteroatomic Rh–Ga/As contacts on the calculated total energy. Interestingly, the orderly distribution of As and Ga that is found in the binary GaAs (Zinc-blende structure type), retained to ternary Rh5Ga2As. The density of states (DOS) and Crystal Orbital Hamiltonian Population (COHP) are calculated to enlighten the stability and bonding characteristics in the structure of Rh5Ga2As. The bonding analysis also confirms that Rh–Ga/As short contacts are the major driving force towards the overall stability of the compound.

scholarly journals First-Principles Modeling of the Smallest Molecular Single Electron Transistor

2015 ◽  
Vol 2 (1) ◽  
pp. 33-39
Author(s):  
Mudassir M. Husain ◽  
Maneesh Kumar
Keyword(s):  
First Principles ◽  
Electron Tunneling ◽  
Energy Levels ◽  
Stability Diagram ◽  
Single Electron ◽  
Single Electron Transistor ◽  
Discrete Energy ◽  
Weakly Coupled ◽  
Electron Transport Properties ◽  
Charging Energy

Using first-principles method the charging energy has been calculated; of the smallest single electron transistor (SET) consisting of only two carbon atoms while operating in coulumb blockade regime. The ethyne (C2H2) molecule is acting like a quantum dot (with discrete energy levels) and is weakly coupled to the gold electrodes (continuum). The quantum effects are significant and the conduction of current takes place through incoherent method via electron tunneling. The electronic levels of the molecule determine the electron transport properties. The molecule may be in several charged states from +2 to -2. It has been observed that the HOMO-LUMO gap is strongly reduced in solid state environment with metallic electrodes, as compared to the vacuum. This reduction is attributed to the image charges generated in the source and drain electrodes. This results in strong localization of charges in the molecule, a phenomenon addressed earlier. The charging energy has been calculated in vacuum and in SET environment. The interaction between molecule and the electrodes is treated self-consistently through Poisson equation. The charge stability diagram of the smallest molecular SET has been obtained.

scholarly journals Electromechanical Characteristics by a Vertical Flip of C70 Fullerene Prolate Spheroid in a Single-Electron Transistor: Hybrid Density Functional Methods

Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2995
Author(s):  
Jong Woan Choi ◽  
Changhoon Lee ◽  
Eiji Osawa ◽  
Ji Young Lee ◽  
Jung Chul Sur ◽  
...  
Keyword(s):  
Density Functional ◽  
Electron Tunneling ◽  
Major Axis ◽  
Prolate Spheroid ◽  
Molecular Orbitals ◽  
Single Electron ◽  
Single Electron Transistor ◽  
Gate Electrode ◽  
Axis Orientation ◽  
Hybrid Density Functional

In this study, the B3LYP hybrid density functional theory was used to investigate the electromechanical characteristics of C70 fullerene with and without point charges to model the effect of the surface of the gate electrode in a C70 single-electron transistor (SET). To understand electron tunneling through C70 fullerene species in a single-C70 transistor, descriptors of geometrical atomic structures and frontier molecular orbitals were analyzed. The findings regarding the node planes of the lowest unoccupied molecular orbitals (LUMOs) of C70 and both the highest occupied molecular orbitals (HOMOs) and the LUMO of the C70 anion suggest that electron tunneling of pristine C70 prolate spheroidal fullerene could be better in the major axis orientation when facing the gate electrode than in the major (longer) axis orientation when facing the Au source and drain electrodes. In addition, we explored the effect on the geometrical atomic structure of C70 by a single-electron addition, in which the maximum change for the distance between two carbon sites of C70 is 0.02 Å.

scholarly journals Finding out square root of an integer number using Single Electron Transistor

2021 ◽  
pp. 96-110
Author(s):  
Dr. Anup Kumar Biswas
Keyword(s):  
Power Consumption ◽  
Gate Voltage ◽  
Large Scale ◽  
Complementary Metal Oxide Semiconductor ◽  
Single Electron ◽  
Oxide Semiconductor ◽  
Integer Number ◽  
Single Electron Transistor ◽  
Square Root ◽  
Ultra Low Power

The single-electron transistor (SET) attracts the researchers, scientists or technologists to design and construct large scale circuits for the sake of the consumption of ultra-low power and its small size. All the incidences in a SET-based circuit happen when only a single electron tunnels through the transistors under the proper applied bias voltage and a small gate voltage or multiple gate voltages. The oscillatory conduction as the function of the variable-multiple /single gate voltage is exhibited by SET. This uncommon characteristic provides the ability of executing the functions of AND, OR, XOR, Inverter and some combinational circuits like multiplexer, subtractor etc. For implementing a square root circuit, SET would be a best candidate to fulfil the requirements. The processing speed of SET based devices will be nearly close to electronic speed. Noise during processing gets ultra-low when the circuits is built with SETs. The square root circuit is presented here for sixteen bit input numbers. The input bit numbers can be increased with the increasing of the depth of the pattern very easily. And this will provide us the greater accuracy about the squared root value. Power consumption in the single electron circuit is low irrespective of bipolar junction transistor (BJT) or Complementary Metal Oxide Semiconductor (CMOS) circuits. Reducing the numbers of nodes, the power consumption is reduced.

A Novel Refrigerator Device Using Single-Electron Pump Applicable to SOI Wafers

2011 ◽  
Vol 222 ◽  
pp. 66-69 ◽  
Author(s):  
Hiroya Ikeda ◽  
Faiz Salleh
Keyword(s):  
Monte Carlo Simulation ◽  
Coulomb Blockade ◽  
Stability Diagram ◽  
Honeycomb Structure ◽  
Silicon On Insulator ◽  
Single Electron ◽  
Single Electron Transfer ◽  
Simulation Based ◽  
Orthodox Theory ◽  
The Stability

We propose a novel single-electron refrigerator (SER) which can be fabricated in silicon-on-insulator wafers. The SER has a structure of single-electron box combined with single-electron pump (SEP). An equivalent circuit of the SEP-refrigerator is represented and its stability diagram (Coulomb diamond) is theoretically calculated. It is found that the stability diagram has a honeycomb structure. Moreover, the operation of the single-electron transfer and single-electron storage is numerically demonstrated using a Monte Carlo simulation based on the orthodox theory of the Coulomb blockade phenomenon.

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