Tetrahedrally bonded ternary and quasi-binary compounds general remarks on band structure and dispersion relations

ABSTRACTOur research on ternary / quaternary chalcogenides for thermoelectric applications has lead to the identification of new interesting compounds and better understanding of the chemistry and physical properties of complex chalcogenides. The chemical, geometric, electronic diversity and flexibility has been well demonstrated in BaBiSe3 and Sr4Bi6Se13 type compounds. This presents both a challenge and more opportunity in controlling and optimizing the thermoelectric properties of these complex chalcogenides, compared with elemental and binary compounds. The importance of multivalley band structure in thermoelectric materials is emphasized. Only compounds with high crystal symmetry have the possibility of having a large number of degenerate valleys in the conduction bands or peaks in the valence bands, respectively. However, most of the complex chalcogenides crystallize in low crystal symmetry. An Edisonian method of exploratory synthesis and characterization may be the working approach to find good thermoelectric materials with ZT higher than 4.

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Band structure nonlocal pseudopotential calculation of the III-nitride wurtzite phase materials system. Part I. Binary compounds GaN, AlN, and InN

Journal of Applied Physics ◽

10.1063/1.1309046 ◽

2000 ◽

Vol 88 (11) ◽

pp. 6467-6475 ◽

Cited By ~ 86

Author(s):

Michele Goano ◽

Enrico Bellotti ◽

Enrico Ghillino ◽

Giovanni Ghione ◽

Kevin F. Brennan

Keyword(s):

Band Structure ◽

Wurtzite Phase ◽

System Part ◽

Binary Compounds

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Tight-binding dispersion of the prismatic pentagonal lattice

International Journal of Modern Physics B ◽

10.1142/s0217979217502733 ◽

2018 ◽

Vol 32 (01) ◽

pp. 1750273

Author(s):

Susobhan Paul ◽

Asim Kumar Ghosh

Keyword(s):

Band Structure ◽

Density Of States ◽

Parameter Space ◽

Tight Binding ◽

Dispersion Relations ◽

Total Density ◽

Zero Energy ◽

Dirac Cone ◽

Analytic Expressions ◽

Total Density Of States

Tight-binding Hamiltonian on the prismatic pentagonal lattice is exactly solved to obtain the analytic expressions of dispersion relations and eigenvectors. This lattice is made of prismatic pentagon which is different from Cairo pentagon. Six different dispersion relations and total density of states are obtained. Dispersion relations are symmetric about the zero energy at a particular point in the parameter space. Although a large gap is found for the Cairo pentagonal lattice, no gap as well as no Dirac cone is found to appear in the tight-binding band structure for this prismatic pentagonal lattice. Instead, a pair of van Hove singularities has been identified at two different energy values in the band structure.

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Thermionic emission laws for general electron dispersion relations and band structure data

Journal of Applied Physics ◽

10.1063/1.5086293 ◽

2019 ◽

Vol 125 (21) ◽

pp. 215105 ◽

Cited By ~ 1

Author(s):

York Christian Gerstenmaier ◽

Gerhard Wachutka

Keyword(s):

Band Structure ◽

Structure Data ◽

Thermionic Emission ◽

Dispersion Relations ◽

Electron Dispersion

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Полупроводниковые гетероструктуры первого рода с непрямой запрещенной зоной на подложках с ориентацией (110)

Физика и техника полупроводников ◽

10.21883/ftp.2019.05.47569.9018 ◽

2019 ◽

Vol 53 (5) ◽

pp. 710

Author(s):

Д.С. Абрамкин ◽

Т.С. Шамирзаев

Keyword(s):

Energy Spectrum ◽

Band Structure ◽

Conduction Band ◽

Strain Distribution ◽

Spin Dynamics ◽

Electronic States ◽

Localized Excitons ◽

Binary Compounds

AbstractType-I indirect-gap heterostructures are convenient objects for studying the spin dynamics of localized excitons, which are difficult to investigate in heterostructures of other types. It is shown that structures with such an energy spectrum can be formed from III–V binary compounds on substrates with the (110) orientation. The effect of the strain distribution and conduction-band structure in quasimomentum space on the energy spectrum of electronic states in the heterostructures is discussed.

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