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Nonreciprocal microwave band-gap structures
Physical Review E, 2002An electrically controlled nonreciprocal electromagnetic band-gap material is proposed and studied. The new material is a periodic three-dimensional regular lattice of small magnetized ferrite spheres. In this paper, we consider plane electromagnetic waves in this medium and design an analytical model for the material parameters. An analytical solution
P A, Belov +2 more
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CLEO/Europe Conference on Lasers and Electro-Optics, 1998
Photonic band gaps are ranges of frequency within which electromagnetic propagation is completely forbidden. They are present in certain materials which possess a periodicity of permittivity at the wavelength scale. Materials with these extreme properties are not known to occur naturally, and.
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Photonic band gaps are ranges of frequency within which electromagnetic propagation is completely forbidden. They are present in certain materials which possess a periodicity of permittivity at the wavelength scale. Materials with these extreme properties are not known to occur naturally, and.
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Direct Band Gap Silicon Allotropes
Journal of the American Chemical Society, 2014Elemental silicon has a large impact on the economy of the modern world and is of fundamental importance in the technological field, particularly in solar cell industry. The great demand of society for new clean energy and the shortcomings of the current silicon solar cells are calling for new materials that can make full use of the solar power.
Qianqian, Wang +7 more
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Band-gap renormalization in quantum wires
Physical Review B, 1993The carrier density dependence and the temporal evolution of the ground level parameters of a quasi-one-dimensional electron-hole plasma confined in GaAs quantum wires have been studied by a line-shape analysis of the time-resolved luminescence.
, Cingolani +7 more
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A dual band gap slotted patch electromagnetic band gap for dual band microstrip antenna
2008 IEEE International RF and Microwave Conference, 2008This paper described the design of the dual band gap slotted patch EBG structure. By introducing double L slot into each EBG patch, a smaller rectangular patch has been introduced in each EBG patch resulting to the achievement of the second stop band frequency. The comparison between mushroom EBG structures has been investigated.
Osman Ayop +2 more
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Study of Band-Gap Characteristics for Curved Electromagnetic Band-Gap Structures
TENCON 2006 - 2006 IEEE Region 10 Conference, 2006According to the reflection condition of optics Bragg, a curved electromagnetic band-gap structures is designed, and the band-gap characteristics of it is studied deeply. The effect of electromagnetic band-gap structure parameters and cylindrical structure parameters on band-gap characteristics are analyzed for the filrst time, and some useful ...
Tao Liu +3 more
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Structural Band Gap Engineering
MRS Proceedings, 1997AbstractIn this paper we discuss a novel approach to the band gap engineering of semiconductors Si, Ge, GaAs and AIN. We suggest that nanoporous polymorphs of these materials may exist which would offer a significant variation of the electronic band gap.
Alexander A. Demkov +2 more
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Engineering acoustic band gaps
Applied Physics Letters, 2001By using a perturbative approach, we propose a simple, systematic, and efficient method to engineer acoustic band gaps. A gap can be enlarged or reduced by altering the microstructure according to the field-energy distributions of the Bloch states at the band edges as well as their derivatives.
Lai, Y., Zhang, XD, Zhang, ZQ
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1990
The distinction between valence and conduction bands is discussed. Insulators, semiconductors, metals. Electrons and holes definition. Effective mass; sign convention of charge, mass and mobility. Semi-metals and narrow gap semiconductors. Band parameters for typical semiconductors, table. Constant energy surfaces in Brillouin zones.
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The distinction between valence and conduction bands is discussed. Insulators, semiconductors, metals. Electrons and holes definition. Effective mass; sign convention of charge, mass and mobility. Semi-metals and narrow gap semiconductors. Band parameters for typical semiconductors, table. Constant energy surfaces in Brillouin zones.
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1995
Wide bandgap materials will have many applications as coatings and as electronic devices. This paper describes an electronic application for wide bandgap materials in energy production. A specific portable power technology which converts the energy emitted from nuclear reactions to electrical energy using wide bandgap photovoltaic cells without ...
M. A. Prelas +3 more
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Wide bandgap materials will have many applications as coatings and as electronic devices. This paper describes an electronic application for wide bandgap materials in energy production. A specific portable power technology which converts the energy emitted from nuclear reactions to electrical energy using wide bandgap photovoltaic cells without ...
M. A. Prelas +3 more
openaire +1 more source