Accurate Tight-Binding Studies of Antiferromagnetic States in La2CuO4

MRS Proceedings ◽

10.1557/proc-141-109 ◽

1988 ◽

Vol 141 ◽

Author(s):

W. E. Pickett ◽

D. A. Papaconstantopoulos

Keyword(s):

Electronic Structure ◽

Band Structure ◽

Spin Polarization ◽

Tight Binding ◽

Antiferromagnetic State ◽

Exchange Field ◽

Exchange Splitting ◽

Binding Studies ◽

Large Anisotropy ◽

D Orbitals

AbstractAn accurate tight-binding parametrization of the electronic structure of La2CuO4 is used to investigate the effects of spin polarization of the Cu ion on the band structure and magnetic moment in the antiferromagnetic state. It is found that when an exchange splitting on the d(x2-y2) orbitals is imposed, a gap in the spectrum is obtained, whereas no gap is found if the splitting is imposed on all of the d orbitals or even on both d(x2 -y2) and d(z2) orbitals. This result suggests large anisotropy of the exchange field on the Cu ion.

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A Tight-Binding Hamiltonian for the High-Temperature Superconductor YBa2Cu3O7

MRS Proceedings ◽

10.1557/proc-141-103 ◽

1988 ◽

Vol 141 ◽

Author(s):

M.J. DeWeert ◽

D.A. Papaconstantopoulos ◽

W.E. Pickett

Keyword(s):

Electronic Structure ◽

High Temperature ◽

Band Structure ◽

Potential Application ◽

Oxygen Vacancies ◽

High Temperature Superconductor ◽

Tight Binding ◽

Coherent Potential Approximation ◽

Potential Approximation

AbstractWe present a highly accurate tight-binding parametrization of the LAPW band structure of the high-temperature superconductor YBa2Cu3O7, discuss the methodology used in obtaining this fit, and its potential application to a Tight-Binding Coherent-Potential Approximation (TB-CPA) calculation of the effects of oxygen vacancies on the electronic structure.

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Tight Binding Modelling of Energy Band Structure in Nitride Heterostructures

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.a223 ◽

2008 ◽

Vol 8 (2) ◽

pp. 540-548 ◽

Cited By ~ 2

Author(s):

Özden Akıncı ◽

H. Hakan Gürel ◽

Hilmi Ünlü

Keyword(s):

Electronic Structure ◽

Band Structure ◽

Valence Band ◽

Nearest Neighbor ◽

Good Description ◽

Energy Levels ◽

Tight Binding ◽

Binding Theory ◽

Orbit Splitting ◽

Atomic Energy Levels

We studied the electronic structure of group III–V nitride ternary/binary heterostructures by using a semi-empirical sp3s* tight binding theory, parametrized to provide accurate description of both valence and conductions bands. It is shown that the sp3s* basis, along with the second nearest neighbor (2NN) interactions, spin-orbit splitting of cation and anion atoms, and nonlinear composition variations of atomic energy levels and bond length of ternary, is sufficient to describe the electronic structure of III–V ternary/binary nitride heterostructures. Comparison with experiment shows that tight binding theory provides good description of band structure of III–V nitride semiconductors. The effect of interface strain on valence band offsets in the conventional Al1−xGaxN/GaN and In1−xGaxN/GaN and dilute GaAs1−xNx/GaAs nitride heterostructures is found to be linear function of composition for the entire composition range (0 ≤ x ≤ 1) because of smaller valence band deformations.

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Symmetry-adapted tight-binding electronic structure analysis of carbon nanotubes with defects, kinks, twist, and stretch

Mathematics and Mechanics of Solids ◽

10.1177/1081286520961831 ◽

2020 ◽

pp. 108128652096183

Author(s):

Soumya Mukherjee ◽

Hossein Pourmatin ◽

Yang Wang ◽

Timothy Breitzman ◽

Kaushik Dayal

Keyword(s):

Carbon Nanotubes ◽

Electronic Structure ◽

Band Structure ◽

Tight Binding ◽

Numerical Approach ◽

Computational Method ◽

Computational Domain ◽

Perfectly Matched Layers ◽

Vacancy Defects ◽

Semiconducting Nanotubes

In this paper, a symmetry-adapted method is applied to examine the influence of deformation and defects on the electronic structure and band structure in carbon nanotubes. First, the symmetry-adapted approach is used to develop the analog of Bloch waves. Building on this, the technique of perfectly matched layers is applied to develop a method to truncate the computational domain of electronic structure calculations without spurious size effects. This provides an efficient and accurate numerical approach to compute the electronic structure and electromechanics of defects in nanotubes. The computational method is applied to study the effect of twist, stretch, and bending, with and without various types of defects, on the band structure of nanotubes. Specifically, the effect of stretch and twist on band structure in defect-free conducting and semiconducting nanotubes is examined, and the interaction with vacancy defects is elucidated. Next, the effect of localized bending or kinking on the electronic structure is studied. Finally, the paper examines the effect of 5–8–5 Stone–Wales defects. In all of these settings, the perfectly matched layer method enables the calculation of localized non-propagating defect modes with energies in the bandgap of the defect-free nanotube.

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Tight-binding studies of the electronic band structure of GaAlN and GaInN alloys

Applied Physics A ◽

10.1007/s00339-004-2930-5 ◽

2005 ◽

Vol 81 (5) ◽

pp. 1029-1033 ◽

Cited By ~ 11

Author(s):

H. Hernández-Cocoletzi ◽

D.A. Contreras-Solorio ◽

J. Arriaga

Keyword(s):

Band Structure ◽

Electronic Band Structure ◽

Tight Binding ◽

Binding Studies ◽

Electronic Band

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Orbitals and bands at metal surfaces: photoemission from the {110} surface of tungsten

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1981.0108 ◽

1981 ◽

Vol 376 (1767) ◽

pp. 565-583 ◽

Cited By ~ 13

Keyword(s):

Electronic Structure ◽

Band Structure ◽

Surface State ◽

Photon Emission ◽

Tight Binding ◽

Tight Binding Approximation ◽

The Third ◽

Surface Brillouin Zone ◽

Orbital Character ◽

Bulk Band

The electronic structure of the {110} surface of tungsten has been investigated by using angle-resolved photoemission. A surface state has been identified and characterized throughout the surface Brillouin zone (s. B. z.). Its dispersion is found to correlate with the projected band gap between the third and fourth bands of the tungsten bulk band structure. It is identified by comparison with Inglesfield’s calculation as having predominantly m = 1 d-orbital character. With photon energies of 21.2 and 40.8 eV, intense photoemission from the surface state is only observed after surface Umklapp, whereas, with 16.8 eV, photon emission is observed in both the first and second s. B. zs. The applicability of the tight-binding approximation to the elucidation of the electronic structure of a metal surface is examined with particular reference to this surface state. A qualitative analysis of the observed photoemission intensities is consistent with emission from a tungsten e g orbital that is hybridized with e g orbitals on neighbouring atoms.

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Electronic Structure of Substitutionally Disordered Alloys: Direct Configurational Averaging

MRS Proceedings ◽

10.1557/proc-278-307 ◽

1992 ◽

Vol 278 ◽

Author(s):

C. Wolverton ◽

D. De Fontaine ◽

H. Dreysse ◽

G. Ceder

Keyword(s):

Electronic Structure ◽

Band Structure ◽

Local Density ◽

Tight Binding ◽

Ternary Alloys ◽

Orbital Method ◽

Thermodynamic Quantities ◽

Local Density Of States ◽

Disordered Alloys ◽

Effective Cluster

AbstractThe method of direct configurational averaging (DCA) has been proposed to study the electronic structure of disordered alloys. Local density of states and band structure energies are obtained by averaging over a small number of configrations within a tight-binding Hamiltonian. Effective cluster interactions, the driving quantities for ordering in solids, are computed for various alloys using a tight-binding form of the linearized muffin-tin orbital method (TB-LMTO). The DCA calculations are used to determine various energetic and thermodynamic quantities for binary and ternary alloys.

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Tight-Binding Study of the Electronic Structure of the high Temperature Superconductor La2CuO4

MRS Proceedings ◽

10.1557/proc-99-447 ◽

1987 ◽

Vol 99 ◽

Author(s):

D. A. Papaconstantopoulos ◽

M. J. Deweert ◽

W. E. Pickett

Keyword(s):

Electronic Structure ◽

High Temperature ◽

Band Structure ◽

Fermi Surface ◽

First Principles ◽

High Temperature Superconductor ◽

Tight Binding ◽

Binding Study ◽

Three Components

ABSTRACTWe have fit our first principles LAPW band structure results for the high Tc superconductor La2CuO4 to a tight-binding Hamiltonian that contains s, p, and d interactions from the three components of these materials. Our fit reproduces very accurately the 17 lower bands of this material and especially the Fermi surface.

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