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- Biblioteca Digitais de Teses e Dissertações da USP
- Sociedade Brasileira de Física
- Brock University
- Universidade de Tubinga
- AMER INST PHYSICS; MELVILLE
- Institute of Physics Publishing
- Universidade Cornell
- American Physical Society
- John Wiley & Sons
- Sociedad Española de Cerámica y Vidrio
- American Association for the Advancement of Science
- Universidade Autônoma de Barcelona
- Elsevier
- Sociedad Mexicana de Física
- Mais Publicadores...

## Determinação de parâmetros para Hamiltonianos k.p a partir de estruturas de bandas pré-existentes; Parameters determination for k.p Hamiltonians from preexistent band structures

Fonte: Biblioteca Digitais de Teses e Dissertações da USP
Publicador: Biblioteca Digitais de Teses e Dissertações da USP

Tipo: Dissertação de Mestrado
Formato: application/pdf

Publicado em 12/02/2015
PT

Relevância na Pesquisa

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#Band structure#Effective masses#Estrutura de bandas#k.p method#Massas efetivas#Método k.p#Semiconductors#Semicondutores

O estudo das estruturas de bandas de energia representa um ponto fundamental no entendimento de alguns fenômenos no âmbito da física do estado sólido, tais como luminescências e transporte, entre outros. Estas estruturas podem ser obtidas de diversas formas: através de medidas experimentais, tais como ARPES,1 ou por modelos teóricos.24 Os modelos teóricos se dividem entre métodos ab initio, como o cálculo DFT,5 e métodos efetivos, como o k.p.6, 7 A abordagem DFT é viável para sistemas que vão de poucos átomos (como por exemplo, materiais bulk ) até centenas de átomos (ou mesmo milhares, com restrições quanto às aproximações necessárias). Para sistemas confinados, por ser necessária uma grande quantidade de átomos, o custo computacional torna-se inviável. No método k.p, por outro lado, as interações são descritas por parâmetros em um Hamiltoniano na forma matricial, geralmente fazendo uso de conceitos de simetria e da Teoria de Grupos. Esses parâmetros, entretanto, são obtidos de forma externa à teoria, através de estruturas de bandas pré-calculadas por outros métodos teóricos ou medidas experimentais. A literatura, porém, não apresenta um método de obtenção dos parâmetros k.p para qualquer estrutura cristalina...

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## Hydrogenated Ge nanocrystals: band gap evolution with increasing size

Fonte: Sociedade Brasileira de Física
Publicador: Sociedade Brasileira de Física

Tipo: Artigo de Revista Científica
Formato: text/html

Publicado em 01/06/2006
EN

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The electronic band structure of various Ge quantum wires of different sizes, with hydrogenated surfaces, is studied using a nearest-neighbor empirical tight-binding Hamiltonian by means of a sp³s* atomic orbitals basis set. We suppose that the nanostructures have the same lattice structure and the same interatomic distance as in bulk Ge and that all the dangling bonds are saturated with hydrogen atoms. These atoms are used to simulate the bonds at the surface of the wire and sweep surface states out of the fundamental gaps. One of the most important features is a clear broadening of the band gap due the quantum confinement. Comparing to experimental data, we conclude that, similar to the case of Si, the size dependent PL in the near infrared may involve a trap in the gap of the nanocrystals.

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## The band structure of Cd0

Fonte: Brock University
Publicador: Brock University

Tipo: Electronic Thesis or Dissertation

ENG

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The Augmented Pl ane Wave Method has been used to
calculate the one-electron energy band structure of CdO.
Energy eigenva l ues were calculated along three symmetry
lines and for some other general wave-vectors of interest.

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## Advanced methods for structural characterization and structure-property correlation for functional materials of layered compounds

Fonte: Universidade de Tubinga
Publicador: Universidade de Tubinga

Tipo: Dissertação

EN

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#Durchstrahlungselektronenmikroskopie , Energiedispersive Röntgenspektroskopie , , Supraleiter#530#atomically resolved scanning transmission electron microscopy#Microstructural characterization#Structure-property correlation#thermoelectricity#band structure#transport tensors#Transporttensoren#Bandstruktur#Struktur-Eigenschafts-Korrelation

A large number of functional materials have layered structures yielding anisotropic physical properties and an exciting physics of extended defects. For the understanding of both phenomena extensive computational methods are necessary for calculating anisotropic physical properties in an ab-initio approach. Calculating high-energy electron scattering is essential to yield quantitative results on defect structures by electron microscopy and spectroscopy. In this thesis superconducting ReBa2Cu3O7-x (ReBCO, Re = rare earth) coated conductors and thermoelectric Bi2Te3-related device-relevant materials were analyzed in detail. For both compounds various computational methods were applied to yield a quantitative structure-property correlation. The microstructure and the chemical composition of a material affecting its macroscopic physical properties is referred to as structure-property correlation.
Coated conductors consist of multilayer thin film structures and are high-temperature superconducting (HTS) wires of the second generation. The analyzed coated conductors were grown by two methods: (i) chemical solution deposition (CSD) and (ii) inclined substrate deposition (ISD). In this work both materials were analyzed and compared to each other...

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## Band structure calculations of InP wurtzite/zinc-blende quantum wells

Fonte: AMER INST PHYSICS; MELVILLE
Publicador: AMER INST PHYSICS; MELVILLE

Tipo: Artigo de Revista Científica

ENG

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#FIELD-EFFECT TRANSISTORS#III-V NANOWIRES#SEMICONDUCTOR NANOWHISKERS#ALGAN/GAN SUPERLATTICES#ELECTRONIC-STRUCTURE#ZINCBLENDE#GROWTH#HETEROSTRUCTURES#CARRIERS#GAN#PHYSICS, APPLIED

Semiconductor nanowhiskers (NWs) made of III-V compounds exhibit great potential for technological applications. Controlling the growth conditions, such as temperature and diameter, it is possible to alternate between zinc-blende (ZB) and wurtzite (WZ) crystalline phases, giving origin to the so called polytypism. This effect has great influence in the electronic and optical properties of the system, generating new forms of confinement to the carriers. A theoretical model capable to accurately describe electronic and optical properties in these polytypical nanostructures can be used to study and develop new kinds of nanodevices. In this study, we present the development of a wurtzite/zinc-blende polytypical model to calculate the electronic band structure of nanowhiskers based on group theory concepts and the k.p method. Although the interest is in polytypical superlattices, the proposed model was applied to a single quantum well of InP to study the physics of the wurtzite/zinc-blende polytypism. By the analysis of our results, some trends can be predicted: spatial carriers' separation, predominance of perpendicular polarization (xy plane) in the luminescence spectra, and interband transition blueshifts with strain. Also, a possible range of values for the wurtzite InP spontaneous polarization is suggested. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4767511]; Brazilian funding agency CAPES; Brazilian funding agency CAPES; Brazilian funding agency CNPq; Brazilian funding agency CNPq; Brazilian funding agency FAPESP; Brazilian funding agency FAPESP

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## Electronic Band Structure of Metallic Calcium Measured by Electron Momentum Spectroscopy

Fonte: Institute of Physics Publishing
Publicador: Institute of Physics Publishing

Tipo: Artigo de Revista Científica

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#Keywords: Band structure#Calcium#Computer simulation#Electron spectroscopy#Electrons#Monte Carlo methods#Electron momentum spectroscopy#Electronic structure

We have measured the bulk energy-momentum resolved conduction band structure of metallic calcium using electron momentum spectroscopy (EMS). From the EMS data we have extracted the band dispersion, occupied bandwidth and density of states. The experimenta

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## Bulk Inversion Asymmetry effects on the band structure of zincblende heterostructures in an 8-band Effective Mass Approximation model

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 17/12/2002

Relevância na Pesquisa

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We have developed an 8-band Effective Mass Approximation model that describes
the zero field spin splitting in the band structure of zincblende
heterostructures due to bulk inversion asymmetry (BIA). We have verified that
our finite difference Hamiltonian transforms in almost all situations according
to the true $D_{2d}$ or $C_{2v}$ symmetry of [001] heterostructures. This makes
it a computationally efficient tool for the accurate description of the band
structure of heterostructures for spintronics. We first compute the band
structure for an AlSb/GaSb/AlSb quantum well (QW), which presents only BIA, and
delineate its effects. We then use our model to find the band structure of an
AlSb/InAs/GaSb/AlSb QW and the relative contribution of structural and bulk
inversion asymmetry to the spin splitting. We clarify statements about the
importance of these contributions and conclude that, even for our small gap QW,
BIA needs to be taken into account for the proper description of the band
structure.; Comment: 14 pages, 15 figures, 6 tables

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## The Antiferromagnetic Band Structure of La2CuO4 Revisited

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

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Using the Becke-3-LYP functional, we have performed band structure
calculations on the high temperature superconductor parent compound, La2CuO4.
Under the restricted spin formalism (rho(alpha) equal to rho(beta)), the
R-B3LYP band structure agrees well with the standard LDA band structure. It is
metallic with a single Cu x2-y2/O p(sigma) band crossing the Fermi level. Under
the unrestricted spin formalism (rho(alpha) not equal to rho(beta)), the UB3LYP
band structure has a spin polarized antiferromagnetic solution with a band gap
of 2.0 eV, agreeing well with experiment. This state is 1.0 eV (per formula
unit) lower than that calculated from the R-B3LYP. The apparent high energy of
the spin restricted state is attributed to an overestimate of on-site Coulomb
repulsion which is corrected in the unrestricted spin calculations. The
stabilization of the total energy with spin polarization arises primarily from
the stabilization of the x2-y2 band, such that the character of the eigenstates
at the top of the valence band in the antiferromagnetic state becomes a strong
mixture of Cu x2-y2/O p(sigma) and Cu z2/O' p(z). Since the Hohenberg-Kohn
theorem requires the spin restricted and spin unrestricted calculations give
exactly the same ground state energy and total density for the exact
functionals...

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## The Importance of Static Correlation in the Band Structure of High Temperature Superconductors

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

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Recently we presented a new band structure for La(2-x)Sr(x)CuO(4) and other
high temperature superconductors in which a second narrow band was seen to
cross the primary band at the Fermi level. The existence of this second Fermi
level band is in complete disagreement with the commonly accepted LDA band
structure. Yet it provided a crucial piece of physics which led to an
explanation for superconductivity and other unusual phenomena in these
materials. In this work we present details as to the nature of the failure of
conventional methods in deriving the band structure of the cuprates. In
particular, we use a number of chemical analogues to describe the problem of
static correlation in the band structure calculations and show how this can be
corrected with the predictable outcome of a Fermi level band crossing.; Comment: The Journal of Physical Chemistry, in press. References and figures
updated. See www.firstprinciples.com for more information related to this
work

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## Phononic band structure of honeycomb lattice with defects, using spectrally formulated finite element method

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 28/09/2015

Relevância na Pesquisa

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A spectrally formulated finite element analysis based methodology has been
proposed to calculate phononic band structure of reticulated honeycomb lattices
having translationally invariant repetitive elements called unit cells. Bloch
formulation captures dynamics of infinite structure through that of a unit
cell. While conventional FEM is generally used for analyzing dynamics of such
unit systems, here, constituent structural members are treated as 1D waveguide
and modeled as Timoshenko beam frame element, enabling application of spectral
FEM, suitable for accurately analyzing the dynamics, particularly efficient at
very high frequencies. Using exact solutions as shape functions spares dense
meshing. Resulting eigenvalue problem is solved by Wittrick-Williams method, an
iterative scheme. Subsequently, band structures are obtained for supercells-
units comprising multiple elemental unit cells; compared and reconciled with
those obtained using elemental cell (termed primitive unit cell to distinguish
from supercell). Primitive cell band structures are reconstructed from
Supercell band structures. Supercell band structures show some spurious bands,
which are explained in terms of band folding in the primitive cell band
structure. Supercell allows treatment of defects as a periodic feature with
certain defect density. Of particular observation in such band structures is
the separation of bands...

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## The band structure and Fermi surface of La$_{0.6}$Sr$_{0.4}$MnO$_{3}$ thin films studied by in-situ angle-resolved photoemission spectroscopy

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 15/03/2005

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We have performed an in situ angle-resolved photoemission spectroscopy
(ARPES) on single-crystal surfaces of La$_{0.6}$Sr$_{0.4}$MnO$_{3}$ (LSMO) thin
films grown on SrTiO$_{3}$ (001) substrates by laser molecular beam epitaxy,
and investigated the electronic structure near the Fermi level ($E_{F}$). The
experimental results were compared with the band-structure calculation based on
LDA + $U$. The band structure of LSMO thin films consists of several highly
dispersive O 2$p$ derived bands in the binding energy range of 2.0 - 6.0 eV and
Mn 3$d$ derived bands near $E_{F}$. ARPES spectra around the $Gamma$ point show
a dispersive band near $E_{F}$ indicative of an electron pocket centered at the
$Gamma$ point, although it was not so clearly resolved as an electronlike
pocket due to the suppression of spectral weight in the vicinity of $E_{F}$.
Compared with the band-structure calculation, the observed conduction band is
assigned to the Mn 3$de_{g}$ majority-spin band responsible for the
half-metallic nature of LSMO. We have found that the estimated size of the
Fermi surface is consistent with the prediction of the band-structure
calculation, while the band width becomes significantly narrower than the
calculation. Also, the intensity near $E_{F}$ is strongly reduced. The origin
of these discrepancies between the experiment and the calculation is discussed.; Comment: 7 pages...

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## Electronic band structure of carbon nanotube superlattices from first-principles calculations

Fonte: American Physical Society
Publicador: American Physical Society

Tipo: Artículo
Formato: 601770 bytes; application/pdf

ENG

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#Ab initio calculations#Band structure#Carbon nanotubes#Fermi level#Superlattices#Tight-binding calculations

7 pp.-- PACS nrs.: 73.22.-f, 73.21.Fg, 73.22.Dj, 71.15.Mb.; We report on first-principles calculations for metallic carbon nanotube superlattices N(12,0)/N(6,6) with N=1–4. Although the calculated band structures show a good overall agreement with the results of the simpler tight-binding π-electron approximation, electron interaction and correlation effects strongly modify some peculiar flatbands, previously found within a tight-binding approach [W. Jaskólski and L. Chico, Phys. Rev. B 71, 155405 (2005)]. In the ab initio approach, these bands are no longer dispersionless, much closer to the Fermi level, and are always nondegenerate, in contrast to former tight-binding results.; Peer reviewed

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## Band structure effects on the Be(0001) acoustic surface plasmon energy dispersion

Fonte: John Wiley & Sons
Publicador: John Wiley & Sons

Tipo: Artículo
Formato: 135660 bytes; application/pdf

ENG

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#Density functional theory, local density approximation, gradient and other corrections#Exchange, correlation, dielectric and magnetic response functions, plasmons#Surface states, band structure, electron density of states#Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)

22 pp.-- PACS nrs.: 71.15.Mb, 71.45.Gm, 73.20.At, 73.20.Mf.-- Pre-print version available at: http://arxiv.org/abs/0806.2364.; We report first-principles calculations of acoustic surface plasmons on the (0001) surface of Be, as obtained in the random-phase approximation of many-body theory. The energy dispersion of these collective excitations has been obtained along two symmetry directions. Our results show a considerable anisotropy of acoustic surface plasmons, and underline the capability of experimental measurements of these plasmons to map the electron-hole excitation spectrum of the quasi two-dimensional Shockley surface state band that is present on the Be(0001) surface.; V.M.S., J.M.P, E.V.C, and P.M.E. acknowledge partial support from the University of the Basque Country (9/UPV 00206.215-13639/2001), the Basque Unibertsitate eta Ikerketa Saila, and the Spanish Ministerio de Educación y Ciencia (MEC) (FIS 2004-06490-C03-01 and CSD2006-53). B.D. and K.P. acknowledge the National
Science Foundation; L.V., L.S., and M.R. Compagnia di San Paolo; P.H. the Danish Natural Science Research Council; D.F. the Programa Ramón y Cajal and Comunidad de Madrid.; Peer reviewed

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## Correlación entre la estructura de bandas y las propiedades físicas de óxidos cerámicos de estructura perovsquita con metales de transición (II): Propiedades magnéticas y electrocatalíticas; Relationship between band structure and Physical properties in transition metal ceramic oxides with perovskite structure: (II) Magnetic and electrocatalytic properties

Fonte: Sociedad Española de Cerámica y Vidrio
Publicador: Sociedad Española de Cerámica y Vidrio

Tipo: Artículo
Formato: 716702 bytes; application/pdf

SPA

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#Óxidos cerámicos de tipo perovsquita#Magnetismo#Catálisis#Estructura de bandas#Ceramic oxides with perovskite structure#Magnetism#Catalysis#Band structure

[ES] Se revisan los principales modelos teóricos y parámetros presentes en la literatura, que pretenden dar una explicación sobre
las propiedades magnéticas y electrocatalíticas de óxidos cerámicos con estructura perovsquita, en los que en la posición B
se encuentran los metales de transición (Fe, Co, Ni, Mn), en relación con su estructura de bandas y el carácter de sus electrones
más externos. Se pretende integrar y dar una visión global clara a dichos modelos inconexos.; [EN] Theoretical models present in literature and developed for the explanation of magnetic and electrocatalytic properties in
transition metal (Fe, Co, Ni, Mn) ceramic oxides with perovskite structure in relation with their band diagram and outer electron
nature have been revised. It is proposed to give an integrated and global idea about of several theoretical models that
have not been yet connected.; Peer reviewed

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## Correlación entre la estructura de bandas y las propiedades físicas de óxidos cerámicos de estructura perovskita con metales de transición (I): Propiedades de conducción electrónica; Band structure and physical properties relationship in transition metal ceramic oxides with perovskite structure (I): Electronic conduction properties

Fonte: Sociedad Española de Cerámica y Vidrio
Publicador: Sociedad Española de Cerámica y Vidrio

Tipo: Artículo
Formato: 744416 bytes; application/pdf

SPA

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#Óxidos cerámicos de tipo perovsquita#Estructura de bandas#Transiciones metal aislante#Ceramic oxides with perovskite structure#Electronic conduction#Band structure#Metal insulator transitions

[ES] En este artículo se revisa los principales modelos teóricos, que pretenden dar una explicación sobre las propiedades de conducción
electrónica de óxidos cerámicos con estructura perovskita, que incluyen en la posición B metales de transición del
primer período (Fe, Co, Ni, Mn), en conexión con su estructura de bandas y el carácter de sus electrones más externos, así
como las transiciones metal aislante. Una continuación de este trabajo (Parte II), tratará lo referente a propiedades magnéticas
y electrocatalíticas intentando integrar los trabajos llevados a cabo en la literatura sobre los campos citados.; [EN] Theoretical models present in the literature and developed for the explanation of electronic conduction properties in transition
metal (Fe, Co, Ni, Mn) ceramic oxides with perovskite structure in relation with their band diagram and outer electron
nature, as well as metal insulator transitions have been revised. The second part of this work will be involved with magnetic
and electrocatalytic properties.; Peer reviewed

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## Band formation from coupled quantum dots formed by a nanoporous network on a copper surface

Fonte: American Association for the Advancement of Science
Publicador: American Association for the Advancement of Science

Tipo: Artículo
Formato: 2039679 bytes; application/pdf

ENG

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#Coupled quantum systems#Quantum dots#Quantum confinement#Crystalline solids#Surfaces#Organic nanoporous network#Electronic band structure#Pore states

4 pages, 3 figures.-- Supporting information (Materials and Methods, SOM Text, Suppl. figs. S1-S7, Suppl Refs, 15 pages) available at: http://science-mag.aaas.org/cgi/data/325/5938/300/DC1/1; The properties of crystalline solids can to a large extent be derived from the scale and dimensionality of periodic arrays of coupled quantum systems such as atoms and molecules. Periodic quantum confinement in two dimensions has been elusive on surfaces, mainly because of the challenge to produce regular nanopatterned structures that can trap electronic states. We report that the two-dimensional free electron gas of the Cu(111) surface state can be trapped within the pores of an organic nanoporous network, which can be regarded as a regular array of quantum dots. Moreover, a shallow dispersive electronic band structure is formed, which is indicative of electronic coupling between neighboring pore states.; Supported by the Swiss National Science Foundation, the National Center of Competence in Research "Nanoscale Science", the European Union through the Marie Curie Research Training
Network PRAIRIES, the Wolfermann-Nägeli-Stiftung, the Bundesministerum für Bildung und Forschung (BMBF) Cluster "Forum Organic Electronics" (Heidelberg), and the Swiss Federal Commission for Technology and Innovation (CTI).; Peer reviewed

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## Tuning the band gap of semiconducting carbon nanotube by an axial magnetic ﬁeld

Fonte: Universidade Autônoma de Barcelona
Publicador: Universidade Autônoma de Barcelona

Tipo: Artigo de Revista Científica
Formato: application/pdf

Publicado em //2010
ENG

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#Carbon nanotubes#Magnetic fields#Band gap#Band structure#Electrodes#Field effect transistors#Semiconductor nanotubes#Nanotube devices#Semiconductor growth#Activation energies

We have investigated the magnetic field dependence of transfer characteristics of a device fabricated in a configuration of a field-effect transistor with a conduction channel formed by a semiconducting multiwalled carbon nanotube. Our results unambiguously indicate that an axial magnetic field suppresses the band gap of the nanotube. Quantitative analysis of the data indicates linear dependence of the band gap on magnetic field as well as a linear splitting between the K and K′ subbands of the band structure of the nanotube.

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## Electronic Band Structure of Calcium Oxide

Fonte: Elsevier
Publicador: Elsevier

Tipo: Artigo de Revista Científica

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#Keywords: Alkaline earth metals#Band structure#Bandwidth#Lime#Microelectronics#Scattering#X ray analysis#X ray photoelectron spectroscopy#Electron momentum spectroscopy#Electron-solid scattering and transition-inelastic#Plane-wave impulse approximation (P Alkaline earth metals

We employed electron momentum spectroscopy (EMS) to measure the bulk electronic structure of calcium oxide. We extracted the electron momentum density (EMD), density of occupied states (DOS), band dispersions, bandwidths and intervalence bandgaps from the data. The results are compared with calculations based on the full potential linear muffin-tin orbital(FP-LMTO) approximation. While the bandwidths of 0.6±0.2 and 1.2±0.1 eV for the s- and p-bands, respectively, and their dispersions agree well with the LMTO calculation, the relative intensity of the two bands is at odds with the theory. The measured intervalence bandgap at the Γ-point of 16.5±0.2 eV is larger by 2.1 eV than that from the LMTO calculation. The experimental bandwidth of the Ca 3p semi-core level of 0.7±0.1 eV agrees with the LMTO prediction. The measured bandgap between this level and the s-band is 3.6±0.2 eV. The Ca 3s-3p level splitting is in excellent agreement with the literature.

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## First-principles calculation of the band gap of Al xGa1-xN and In xGa1-x N

Fonte: Sociedad Mexicana de Física
Publicador: Sociedad Mexicana de Física

Tipo: Artigo de Revista Científica
Formato: text/html

Publicado em 01/11/2008
EN

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Ab-initio calculations of the band gap variation of Al xGa1-xN and In xGa1-x N ternary compounds were carried out using the Full-Potential Linearized Augmented Plane Waves (FLAPW) method, within the Density Functional Theory (DFT). These nitrides were modeled in their wurtzite structure using the supercell method, for concentrations x = 0, 0.25, 0.50, 0.75 and 1.0. To optimize the cell parameters of the binary compounds we used the PBE96 (Perdew et al., Phys. Rev. Lett. 77 (1996) 3865) exchange-correlation functional. For the band structure calculations, we used both PBE96 and EV93 (Engel et al., Phys. Rev. B 47 (1993) 13164) exchange-correlation functionals. We considered experimental and calculated (with PBE96) lattice parameters to work out the electronic properties. We found that the fundamental gap is direct in all compounds. The calculation with EV93 functional gives a better band gap estimation for binary nitrides. The bowing parameter was also estimated obtaining the values b = 0.74 eV for Al xGa1-xN and b = 2.12 eV for In xGa1-x N.

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## First-principles study of electronic structure of Bi2Sr2Ca2Cu3O10

Fonte: Sociedad Mexicana de Física
Publicador: Sociedad Mexicana de Física

Tipo: Artigo de Revista Científica
Formato: text/html

Publicado em 01/02/2014
EN

Relevância na Pesquisa

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We present for the first time the electronic structure calculation of Bi2Sr2Ca2Cu3O10 compound in the tetragonal structure (space group 14/mmm). We used the Local Density Approximation (LDA) as in the Wien2k code. We analyze in detail the band structure, density of states, and Fermi surface (FS) for this compound. The FS calculated shows the feature known as the Bi-O pocket problem which we associate with the interaction of the Cu2-O2 and Bi-O4 planes through O3 atoms. However, our FS in the nodal direction is in very good agreement with the FS measured using angle-resolved photo-emission spectroscopy (ARPES). This calculation is useful, since Bi2Sr2Ca2Cu3O10 compound show a transition to the superconducting state at ~ 110 K and to date there are no reports in the literature of its electronic structure known to us.

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