scholarly journals The Ground Binding Energy of a Center Hydrogenic Impurity in Spherical GaAs Quantum Dots

2017 ◽  
Vol 07 (04) ◽  
pp. 155-162
Author(s):  
真梅 陈
2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Guangxin Wang ◽  
Xiuzhi Duan ◽  
Wei Chen

Within the framework of the effective mass approximation, barrier thickness and hydrostatic pressure effects on the ground-state binding energy of hydrogenic impurity are investigated in wurtzite (WZ) GaN/AlxGa1−xN strained quantum dots (QDs) by means of a variational approach. The hydrostatic pressure dependence of physical parameters such as electron effective mass, energy band gaps, lattice constants, and dielectric constants is considered in the calculations. Numerical results show that the donor binding energy for any impurity position increases when the hydrostatic pressure increases. The donor binding energy for the impurity located at the central of the QD increases firstly and then begins to drop quickly with the decrease of QD radius (height) in strong built-in electric fields. Moreover, the influence of barrier thickness along the QD growth direction and Al concentration on donor binding energy is also investigated. In addition, we also found that impurity positions have great influence on the donor binding energy.


2010 ◽  
Vol 24 (22) ◽  
pp. 4293-4304 ◽  
Author(s):  
SHENG WANG ◽  
GUOZHU WEI ◽  
GUANGYU YI

The ground-state binding energies of a hydrogenic impurity in cylindrical quantum dots (QDs) subjected to external electric and magnetic fields are investigated using the finite-difference method within the quasi-one-dimensional effective potential model. The QD is modeled by superposing a square-well potential and a strong lateral confinement potential by the combination of a parabolic potential and a changeable magnetic field. We define an effective radius of a cylindrical QD which can describe the strength of the lateral confinement. The effects of the electric fields are less important when the effective radius is very tiny, and the effects are manifested as the effective radius increases. Meanwhile, one finds that the binding energies highly depend on the impurity positions under the applied transverse fields. When the impurity is located at the right half of the cylinder, the electric field pushes the electron to the left side, then the binding energy decreases; when the impurity is located at the left, the binding energy first increases and reaches a peak value, then deceases with the electric field.


2011 ◽  
Vol 20 (12) ◽  
pp. 127301 ◽  
Author(s):  
Hong Zhang ◽  
Xue Wang ◽  
Jian-Feng Zhao ◽  
Jian-Jun Liu

2016 ◽  
pp. 4024-4028 ◽  
Author(s):  
Sergey I. Pokutnyi ◽  
Wlodzimierz Salejda

The possibility of occurrence of the excitonic  quasimolecule formed of spatially separated electrons and holes in a nanosystem that consists  of  CuO quantum dots synthesized in a silicate glass matrix. It is shown that the major contribution to the excitonic quasimolecule binding energy is made by the energy of the exchange interaction of electrons with holes and this contribution is much more substantial than the contribution of the energy of Coulomb interaction between the electrons and holes.


2007 ◽  
Vol 06 (05) ◽  
pp. 353-356
Author(s):  
A. I. YAKIMOV ◽  
A. V. DVURECHENSKII ◽  
A. I. NIKIFOROV ◽  
A. A. BLOSHKIN

Space-charge spectroscopy was employed to study electronic structure in a stack of four layers of Ge quantum dots coherently embedded in an n-type Si (001) matrix. Evidence for an electron confinement in the vicinity of Ge dots was found. From the frequency-dependent measurements the electron binding energy was determined to be ~50 meV, which is consistent with the results of numerical analysis. The data are explained by a modification of the conduction band alignment induced by inhomogeneous tensile strain in Si around the buried Ge dots.


2015 ◽  
Vol 49 (10) ◽  
pp. 1311-1315 ◽  
Author(s):  
S. I. Pokutnyi ◽  
Yu. N. Kulchin ◽  
V. P. Dzyuba
Keyword(s):  

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