Results 211 to 220 of about 26,906 (267)

Electronic structure of quantum dots

Reviews of Modern Physics, 2002
The properties of quasi-two-dimensional semiconductor quantum dots are reviewed. Experimental techniques for measuring the electronic shell structure and the effect of magnetic fields are briefly described. The electronic structure is analyzed in terms of simple single-particle models, density-functional theory, and "exact" diagonalization methods. The
Reimann,Stephanie M., Manninen, Matti
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Quantum dots in quantum well structures

Journal of Luminescence, 1996
Abstract Recent progress toward fabricating and characterizing quantum dots in III–V quantum well structures is reviewed. Quantum dots made by use of lithography and etching, including deep-etched, barrier-modulated, strain-induced and interdiffused quantum dots, are described.
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Dynamical behavior in a quantum-dot structure

Physical Review B, 1994
Quantum-dot structures can exhibit bistability between two conduction states connected with S-shaped current-voltage characteristics. In this work, a dynamical model for the electric transport in this structure is proposed. Switching times of about 5 ps at threshold are found for small sample capacitances.
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Creation and Structure of Quantum Dots

1998
Unlike quantum wells, where the motion of carriers is restricted to a plane through the crystallization of thin epitaxial layers [64], the creation of quantum wires or dots, which confine the carriers to a space with at least two of three dimensions limited to the range of the de Broglie wavelength, requires far more advanced technology.
Lucjan Jacak, Arkadiusz Wöjs, Paweł Hawrylak   +2 more
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Electronic structure of ellipsoidally deformed quantum dots

Journal of Physics: Condensed Matter, 2001
Using a three-dimensional local spin-density functional method, we investigate the electronic structure of quasi two-dimensional ellipsoidal quantum dots with elliptical deformation. Changes in the electron addition energy spectra and spin polarization are investigated as a function of the number of electrons and the elliptical deformation on the ...
Lee, IH, Kim, YH Kim, Yong-Hoon, Ahn, KH
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The Atomic Structure of Quantum Dots

2008
In this chapter, the atomic structure of both uncapped and buried quantum dots is described as derived from scanning tunneling microscopy in both top-view and cross-sectional geometry. Important conclusions are drawn also on the growth processes during quantum dot formation as well as during overgrowth.
Mario Dähne, Holger Eisele, Karl Jacobi
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Structure and ordering of GaN quantum dot multilayers

Applied Physics Letters, 2001
Grazing incidence x-ray techniques are used to characterize the structure of multilayered GaN quantum dots in an AlN matrix. For a dot lateral size of 170 Å, the values of the interdot vertical and lateral correlation lengths are 1500 and 250 Å, respectively. The presence of smaller quantum dots is observed only in the layers deposited first.
Chamard, Virginie, Metzger, T. H., Bellet-Amalric, E., Daudin, B., Adelmann, C., Mariette, H., Mula, G.   +6 more
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Electronic Structures of InN/GaN Quantum Dots

Journal of Nanoscience and Nanotechnology, 2009
In this letter, ab-initio calculations are performed to study the electronic structures of the InN quantum dot embedded in the GaN matrix. By analyzing the site-decomposed densities of states, an anisotropic potential well in the dot region is clearly depicted.
Chen, S. S., Lin, W., Li, S. P., Kang, J. Y.   +3 more
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Electroluminescence of Si Quantum Dots in MOS Structures

Solid State Phenomena, 2001
We have studied the structural, electrical and optical properties of MOS devices, where the dielectric layer consists of a substoichiometric SiOx (x < 2) thin film deposited by plasma enhanced chemical vapor deposition. After deposition the SiOx samples were annealed at 1250 degreesC for I h; the thermal treatment induces the separation of the Si and ...
A Irrera, G Franzò, E Ceretta Moreira, F Iacona, F Priolo   +4 more
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Excitons in Quantum-Dot Quantum Well Structures

2000
The energy levels and excitation spectra of multi-shell nanocrystals composed of ZnS and CdS layers are investigated. The calculations are performed both in the 6-band envelope function approximation and in the tight-binding approach. Charge separation of pair states, with the electron and hole in different layers, is observed in a number of structures.
W. Jaskólski, Garnett W. Bryant
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