Electronic and thermal properties of silicene nanoribbons: Third nearest neighbor tight binding approximation

Carbon nanotubes (CNTs) have been proved to have promising applicability in various fields of science and technology. Their fascinating mechanical, electrical, thermal, optical properties have caught the attention of today’s world. We have discussed here the great possibility of using CNTs in electronic devices. CNTs can be both metallic and semiconducting depending on their chirality. When two CNTs of different chirality are joined together via topological defects, they may acquire rectifying diode property. We have joined two tubes of different chiralities through circumferential Stone–Wales defects and calculated their density of states by nearest neighbor tight binding approximation. Transmission function is also calculated to analyze whether the junctions can be used as electronic devices. Different heterojunctions are modeled and analyzed in this study. Internal stresses in the heterojunctions are also calculated by molecular dynamics simulation.

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Empirical Tight-Binding Applied to Silicon Nanoclusters

MRS Proceedings ◽

10.1557/proc-491-299 ◽

1997 ◽

Vol 491 ◽

Cited By ~ 2

Author(s):

G. Allan ◽

C. Delerue ◽

M. Lannoo

Keyword(s):

Band Structure ◽

Nearest Neighbor ◽

Good Description ◽

Tight Binding ◽

Localized States ◽

Basis Set ◽

Band Structure Calculation ◽

Minimal Basis ◽

Tight Binding Approximation ◽

Bulk Band

ABSTRACTThe calculation of the electronic structure of silicon nanostructures is used to discuss the accuracy of results obtained by the tight-binding method. We first show that the level of refinement of the tight-binding approximation must be adapted to the calculated property. For example, an accurate description of both the valence and conduction bands which can be achieved with a 3rd-nearest neighbor approximation is necessary to calculate the variation of the gap energy with the silicon crystallite size. The sp3s* model which gives a bad description of the conduction band underestimates the confinement energy but can give good results when it is used to determine the variation of the crystallite band gap with pressure. To study Si-III (BC-8) nanocrystallites, we show that a good description of the bulk band structure can be obtained with non-orthogonal tight-binding but due to the large number of nearest neighbors one must take analytical variations of the parameter with interatomic distances. The parameters involved in these expressions can be easily fitted to the bulk band structures using the k-point symmetry without requiring the use of group theory. Finally we discuss the effect of increasing the size of the minimal-basis set and we show that it would be possible to get the values of the tight-binding parameters from a first-principles localized states band structure calculation avoiding the fit to the energy dispersion curves.

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LOCAL ELECTRONIC STRUCTURE OF Tl2Ca2Ba2Cu3O10 AND COMPARISON WITH LA-OXIDES AND Y-OXIDES

International Journal of Modern Physics B ◽

10.1142/s0217979290000760 ◽

1990 ◽

Vol 04 (09) ◽

pp. 1537-1549 ◽

Cited By ~ 2

Author(s):

HUAI-YU WANG ◽

FU-SUI LIU ◽

EN-GE WANG ◽

CHONG-YU WANG

Keyword(s):

Electronic Structure ◽

Nearest Neighbor ◽

Tight Binding ◽

The Other ◽

Tight Binding Approximation ◽

Densities Of States ◽

Local Electronic Structure ◽

Electronic Densities

Local electronic densities of states of Tl 2 Ca 2 Ba 2 Cu 3 O 10 (2223) are calculated by tight-binding approximation. The nearest and the next-nearest neighbor transitions are considered, and the results are compared with each other. After the latter is considered, the densities of states are smoothened and the semiconductor-like characteristic of the Tl-O layers disappears. Through comparison of 2223 with the other two high Tc ceramics La 2−x Sr x CuO 4 and YBa 2 Cu 3 O 7−x, it is believed that they have the same leading superconductive mechanism besides inter-plane interactions.

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BAND STRUCTURE OF RHOMBOHEDRAL GRAPHITE

Canadian Journal of Physics ◽

10.1139/p58-036 ◽

1958 ◽

Vol 36 (3) ◽

pp. 352-362 ◽

Cited By ~ 80

Author(s):

R. R. Haering

Keyword(s):

Band Structure ◽

Fermi Surface ◽

Nearest Neighbor ◽

Tight Binding ◽

Rhombohedral Structure ◽

Hexagonal Prism ◽

Exchange Integral ◽

Tight Binding Approximation ◽

Out Of Plane ◽

Bernal Stacking

The band structure of rhombohedral graphite has been investigated using the nearest-neighbor tight-binding approximation. The resulting behavior of the π-bands near the Fermi surface is more complex than in the case of the Bernal stacking. The two π-bands still touch, but the touching points no longer lie on the edges of a hexagonal prism in k-space. Instead, they lie on cylinders whose axes are the edges of the hexagonal prism. The radii of these cylinders are proportional to γ1, the nearest "out-of-plane" exchange integral. The de Haas – Van Alphen effect in the rhombohedral structure may be expected to yield useful information about the magnitude of γ1.

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Tight-binding Calculations of Band Structure and Conductance in Graphene Nano-ribbons

Communications in Physics ◽

10.15625/0868-3166/19/1/232 ◽

2009 ◽

Vol 19 (1) ◽

pp. 1-8 ◽

Cited By ~ 5

Author(s):

Hoang Manh Tien ◽

Nguyen Hai Chau ◽

Phan Thi Kim Loan

Keyword(s):

Band Structure ◽

Electronic Properties ◽

Nearest Neighbor ◽

Graphene Nanoribbons ◽

Tight Binding ◽

Numerical Calculations ◽

Dimensional System ◽

Tight Binding Approximation ◽

One Dimensional ◽

Edge Conditions

We suggest a general approach based on the nearest-neighbor tight-binding approximation (TB) to investigate the band structure and conductance of a quasi-one dimensional system. Numerical calculations carried out for Graphene nanoribbons (GNRs) with different widths and edge conditions (zigzag and armchair) reveal the well-known results that the electronic properties of GNRs depend strongly on the size and geometry of the sample.

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Enhancement of thermoelectric figure of merit in zigzag graphene nanoribbons with periodic edge vacancies

International Journal of Modern Physics B ◽

10.1142/s0217979217501247 ◽

2017 ◽

Vol 31 (15) ◽

pp. 1750124 ◽

Cited By ~ 3

Author(s):

D. V. Kolesnikov ◽

O. G. Sadykova ◽

V. A. Osipov

Keyword(s):

Seebeck Coefficient ◽

Figure Of Merit ◽

Nearest Neighbor ◽

Graphene Nanoribbons ◽

Tight Binding ◽

Dynamical Matrix ◽

Thermoelectric Figure Of Merit ◽

Thermoelectric Figure ◽

Tight Binding Approximation ◽

Zigzag Graphene Nanoribbons

The influence of periodic edge vacancies and antidot arrays on the thermoelectric properties of zigzag graphene nanoribbons (ZGNRs) are investigated. Using Green’s function method, the tight-binding approximation for the electron Hamiltonian and the 4th nearest neighbor approximation for the phonon dynamical matrix, we calculate the Seebeck coefficient and the thermoelectric figure of merit. It is found that, at a certain periodic arrangement of vacancies on both edges of zigzag nanoribbon, a finite band gap opens and almost twofold degenerate energy levels appear. As a result, a marked increase in the Seebeck coefficient takes place. It is shown that an additional enhancement of the thermoelectric figure of merit can be achieved by a combination of periodic edge defects with an antidot array.

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Robust and controllable electronic local transports in armchair silicene nanoribbons under a perpendicular electric field

International Journal of Modern Physics B ◽

10.1142/s0217979217501466 ◽

2017 ◽

Vol 31 (21) ◽

pp. 1750146 ◽

Cited By ~ 2

Author(s):

Xiongwen Chen ◽

Zhengang Shi ◽

Baoju Chen ◽

Kehui Song

Keyword(s):

Electric Field ◽

Graphene Nanoribbons ◽

Tight Binding ◽

Structural Defects ◽

Tight Binding Approximation ◽

Current Switch ◽

Densities Of States ◽

Silicene Nanoribbons ◽

Local Densities ◽

Transport Channels

We study the electronic local distribution and transports in pristine armchair-edge silicene nanoribbons (ASiNRs) based on the tight-binding approximation. By calculating the local densities of states at different sites and the bond current between two adjacent sites, we show that comparing to the pristine armchair-edge graphene nanoribbons, a similar “[Formula: see text]” rule and multiple low-electron transport channels exist in the pristine [Formula: see text]-ASiNRs. However, differently, they are controllable to appear and disappear by applying an electric field perpendicular to the ribbon plane. Therefore, one can manipulate the semiconducting channels and realize the current switch “on/off,” unchanging their structures. Moreover, the results are robust against the edge-passivation and a few structural defects, which ensures their stability for the practical application in the silicene-based device.

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