Results 251 to 260 of about 177,744 (299)

Bound polarons in quantum dot quantum well structures

Chinese Physics B, 2009
The problem of bound polarons in quantum dot quantum well (QDQW) structures is studied theoretically. The eigenfrequencies of bulk longitudinal optical (LO) and surface optical (SO) modes are derived in the framework of the dielectric continuum approximation.
Xing Yan, Wang Zhi-Ping, Wang Xu
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Electronic structure of nanocrystal quantum-dot quantum wells

Physical Review B, 2006
The electronic states of $\mathrm{Cd}\mathrm{S}∕\mathrm{Cd}\mathrm{Se}∕\mathrm{Cd}\mathrm{S}$ colloidal nanocrystal quantum-dot quantum wells are studied by large-scale pseudopotential local density approximation (LDA) calculations. Using this approach, we determine the effects of CdS core size, CdSe well thickness, and CdS shell thickness on the band ...
Schrier, Joshua, Wang, Lin-Wang
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Quantum Devices Using Multi-Dots Structures

Quantum Optoelectronics, 1997
Nowadays, due to the advances in nanolithography technology it is possible to fabricate structures whose electronic properties correspond to that of a quasi-one-dimensional electron gas. Such structures allow us to observe ballistic quantum transport at low temperatures, and remarkable experimental observations have resulted1.
E. A. M. Fagotto, S. M. Rossi, E. Moschim   +2 more
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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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Interdiffusion in Semiconductor Quantum Dot Structures

MRS Proceedings, 2002
ABSTRACTThe potential profile of InGaAs quantum dots (QDs) was shown to be easily modified with annealing. We also demonstrate the use of spin-on-glass to create interdiffusion in QDs but the degree of interdiffusion was strongly dependent on the properties of the oxide.
P. Lever, L. Fu, C. Jagadish, M. Gal, H.H. Tan   +4 more
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Phonons in InAs quantum dot structures

physica status solidi c, 2009
AbstractWe present a Raman study of the phonon spectra of periodical structures with (In,Ga)As QDs in (Al,Ga)As matrix as well as AlAs QDs embedded in InAs grown by molecular beam epitaxy. Raman scattering by optical, interface and acoustic phonons was observed in the QD structures.
Alexander Milekhin, Alexander Toropov, Dietrich R. T. Zahn   +2 more
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Kondo transport through a quantum dot coupled with side quantum-dot structures

Chinese Physics B, 2010
This paper investigates Kondo transport properties in a quadruple quantum dot (QD) based on the slave-boson mean field theory and the non-equilibrium Green's function. In the quadruple QD structure one Kondo-type QD sandwiched between two leads is side coupled to two separate QD structures: a single-QD atom and a double-QD molecule.
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Heteropolytype structures with SiC quantum dots

Technical Physics Letters, 2005
Epitaxial silicon carbide layers of 3C-SiC polytype with an array of nanodimensional SiC quantum dots (QDs) have been obtained for the first time using an improved method of sublimation epitaxy in vacuum. The X-ray topography and X-ray diffraction data unambiguously confirm the formation of a 3C-SiC epilayer with twinned regions on the surface of a 6H ...
A. A. Lebedev, V. N. Petrov, A. N. Titkov, L. M. Sorokin, A. S. Tregubova, G. N. Mosina, A. E. Cherenkov, M. P. Shcheglov   +7 more
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Bismides: 2D structures and quantum dots

Journal of Physics D: Applied Physics, 2017
The growth and characterization of ternary GaAsBi and quaternary GaInAsBi compound quantum wells (QWs) on GaAs substrates is presented in this study. The influence of technological parameters, such as different growth modes, substrate temperatures, beam equivalent pressure ratios and thermal treating on structural and luminescent properties of QWs is ...
Vaidas Pačebutas, Renata Butkutė, Bronislovas Čechavičius, Sandra Stanionytė, Evelina Pozingytė, Martynas Skapas, Algirdas Selskis, Andrejus Geižutis, Arūnas Krotkus   +8 more
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Carrier heating in quantum dot structures

Modern Physics Letters B, 2014
In this paper, the effect of carrier heating (CH) in the four-wave mixing theory in quantum dot (QD) structure has been studied. The influence of parameters such as CH nonlinear gain parameter, wetting layer carrier density, CH time constant, QD ground and excited state energies have been examined. Our model predicts a low CH for QDs which can explain
Ahmed H. Flayyih, Amin H. Al-Khursan
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