Influence of Al Composition on Donor Impurity States in Self-Formed GaAs-AlxGa1-xAs Quantum Rings

2013 ◽  
Vol 380-384 ◽  
pp. 4284-4289
Author(s):  
Guang Xin Wang ◽  
Xiu Zhi Duan
Keyword(s):  
Binding Energy ◽  
Electric Field ◽  
Growth Direction ◽  
Uniform Electric Field ◽  
Donor Impurity ◽  
Impurity States ◽  
Quantum Rings ◽  
Mass Approximation ◽  
Donor Binding Energy ◽  
Special Value

Based on the the effective mass approximation and variational approach, the donor impurity states confined in self-formed GaAs/AlxGa1-xAs quantum rings (QRs) are investigated theoretically. A uniform electric field is applied along the growth direction of the QR. The different effective masses in the different regions of the GaAs/AlxGa1-xAs QR are taken into consideration. Numerical results show that the binding energy of a donor impurity increases gradually, reaches a maximum value, and then decreases quickly to the special value as the QR height decreases. Given a fixed QR size, the binding energy increases for the impurity located at the center of the QR when the Al composition increases. In addition, it can also be found that when the applied electric field strength increases, the donor binding energy increases for impurities localized at the negative z axis of the QR; however, the donor binding energy decreases slightly for impurities located at the center and positive z axis of the QR.

scholarly journals Hydrostatic Pressure and Built-In Electric Field Effects on the Donor Impurity States in Cylindrical Wurtzite GaN/AlxGa1−xN Quantum Rings

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Guangxin Wang ◽  
Xiuzhi Duan ◽  
Rui Zhou
Keyword(s):  
Hydrostatic Pressure ◽  
Binding Energy ◽  
Electric Field ◽  
Growth Direction ◽  
Quantum Ring ◽  
Hydrogenic Impurity ◽  
Mass Approximation ◽  
Donor Binding Energy ◽  
Radial Thickness ◽  
Physical Reasons

Within the framework of the effective mass approximation, the ground-state binding energy of a hydrogenic impurity is investigated in cylindrical wurtzite GaN/AlxGa1-xNstrained quantum ring (QR) by means of a variational approach, considering the influence of the applied hydrostatic pressure along the QR growth direction and the strong built-in electric field (BEF) due to the piezoelectricity and spontaneous polarization. Numerical results show that the donor binding energy for a central impurity increases inchmeal firstly as the QR radial thickness(ΔR)decreases gradually and then begins to drop quickly. In addition, the donor binding energy is an increasing (a decreasing) function of the inner radius (height). It is also found that the donor binding energy increases almost linearly with the increment of the applied hydrostatic pressure. Moreover, we also found that impurity positions have an important influence on the donor binding energy. The physical reasons have been analyzed in detail.

THE EFFECTS OF QUANTUM CONFINEMENT ON THE BINDING ENERGY OF HYDROGENIC IMPURITIES IN A SPHERICAL QUANTUM DOT

2006 ◽  
Vol 20 (18) ◽  
pp. 1127-1134 ◽  
Author(s):  
A. JOHN PETER
Keyword(s):  
Binding Energy ◽  
Quantum Dot ◽  
Shallow Donor ◽  
Donor Impurity ◽  
Hydrogenic Impurity ◽  
Spherical Quantum Dot ◽  
Impurity Position ◽  
Mass Approximation ◽  
Donor Binding Energy ◽  
Parabolic Confinement

The binding energy of a shallow hydrogenic impurity of a spherical quantum dot confined by harmonic oscillator-like and by rectangular well-like potentials, using a variational procedure within the effective mass approximation, has been determined. The calculations of the binding energy of the donor impurity as a function of the system geometry, and the donor impurity position have been investigated. The binding energy of shallow donor impurity depends not only on the quantum confinements but also on the impurity position. Our results reveal that (i) the donor binding energy decreases as the dot size increases irrespective of the impurity position, and (ii) the binding energy values of rectangular confinement are larger than the values of parabolic confinement and (iii) the rectangular confinement is better than the parabolic confinement in a spherical quantum dot.

Binding Energy of Donor Impurity in a Rectangular Semiconductor GaAs Quantum Dot with Electric Field

2014 ◽  
Vol 687-691 ◽  
pp. 3407-3410
Author(s):  
Kang Yun ◽  
Sheng Wang ◽  
Xian Li Li
Keyword(s):  
Binding Energy ◽  
Quantum Dot ◽  
Electric Field ◽  
Potential Model ◽  
Binding Energies ◽  
Zero Field ◽  
Donor Impurity ◽  
One Dimensional ◽  
Mass Approximation ◽  
Gaas Quantum Dot

Within the quasi-one-dimensional effective potential model and effective mass approximation, we calculate the ground and the first few excited state binding energies of a donor impurity in a rectangular quantum dot (RQD) in the presence of electric field. We discuss detailedly dependence of the binding energies on the impurity positions. The results show that the binding energy is the largest when the impurity is located at the center of RQD with zero field and is lowest when the impurity is located at the corner of the RQD. The peak strengths and positions of the probability density in RQD appear to be the critical control on such impurity-induced dependence. We believe our results can provide an indication for design of some photoelectric devices constructed based on GaAs RQD structures.

External electric field effect on the binding energy of a hydrogenic donor impurity in InGaAsP/InP concentric double quantum rings

2018 ◽  
Vol 32 (11) ◽  
pp. 1850138 ◽  
Author(s):  
Min Hu ◽  
Hailong Wang ◽  
Qian Gong ◽  
Shumin Wang
Keyword(s):  
Binding Energy ◽  
Electric Field ◽  
External Electric Field ◽  
Double Quantum ◽  
Electric Field Effect ◽  
Donor Impurity ◽  
Quantum Rings ◽  
Hydrogenic Donor Impurity ◽  
Hydrogenic Donor ◽  
Peak Value

Within the framework of effective-mass envelope-function theory, the ground state binding energy of a hydrogenic donor impurity is calculated in the InGaAsP/InP concentric double quantum rings (CDQRs) using the plane wave method. The effects of geometry, impurity position, external electric field and alloy composition on binding energy are considered. It is shown that the peak value of the binding energy appears in two rings with large gap as the donor impurity moves along the radial direction. The binding energy reaches the peak value at the center of ring height when the donor impurity moves along the axial direction. The binding energy shows nonlinear variation with the increase of ring height. With the external electric field applied along the z-axis, the binding energy of the donor impurity located at z[Formula: see text] decreases while that located at z[Formula: see text] increases. In addition, the binding energy decreases with increasing Ga composition, but increases with the increasing As composition.

HYDROGENIC IMPURITY STATES IN WURTZITE ZnO/MgZnO QUANTUM DOT

2010 ◽  
Vol 24 (28) ◽  
pp. 2793-2801
Author(s):  
ZAIPING ZENG ◽  
SHUYI WEI ◽  
JINGBO WEI
Keyword(s):  
Binding Energy ◽  
Quantum Dot ◽  
Electric Field ◽  
Ground State ◽  
Asymmetric Distribution ◽  
Electric Field Effect ◽  
Hydrogenic Impurity ◽  
Mass Approximation ◽  
Donor Binding Energy ◽  
The Right

Based on the effective-mass approximation, considering the built-in electric field effect due to the spontaneous and piezoelectric polarizations, the ground-state donor binding energy of a hygrogenic impurity in a cylindrical wurzite (WZ) ZnO / MgZnO strained quantum dot (QD) is investigated variationally. Numerical results show that the ground-state donor binding energy is highly dependent on the Mg composition, the impurity positions and the QD size. The built-in electric field also induces an asymmetric distribution of the ground-state donor binding energy with respect to the center of the QD. In particular, it is found that the ground-state donor binding energy is insensible to the dot height when the impurity is located at the right boundary of the WZ ZnO / MgZnO strained QD if the dot height is large.

BINDING ENERGY FOR A SHALLOW DONOR IMPURITY IN GaAs–(Ga, Al)As QUANTUM WELLS UNDER HYDROSTATIC PRESSURE AND APPLIED ELECTRIC FIELD

2002 ◽  
Vol 09 (05n06) ◽  
pp. 1753-1756 ◽  
Author(s):  
A. MONTES ◽  
A. L. MORALES ◽  
C. A. DUQUE
Keyword(s):  
Wave Function ◽  
Hydrostatic Pressure ◽  
Binding Energy ◽  
Electric Field ◽  
Quantum Wells ◽  
Applied Electric Field ◽  
Shallow Donor ◽  
Donor Impurity ◽  
External Hydrostatic Pressure ◽  
Mass Approximation

The present work investigates the effects of the hydrostatic pressure and the external applied electric field on the binding energy for shallow donor impurities in GaAs–Ga 1 - x Al x As quantum wells. The effective mass approximation is used and a trial envelope wave function is adopted for the impurity carrier. For fixed well width and applied electric field, the binding energy of the shallow donor impurity is enhanced by increasing the external hydrostatic pressure, and for fixed well width and hydrostatic pressure, the binding energy decreases by increasing the external electric field.

EXTERNAL ELECTRIC FIELD EFFECT ON THE HYDROGENIC DONOR IMPURITY IN ZINC-BLENDE GaN/AlGaN CYLINDRICAL QUANTUM WELL WIRE

2010 ◽  
Vol 24 (23) ◽  
pp. 2413-2421 ◽  
Author(s):  
LIMING JIANG ◽  
JIANMENG SUN
Keyword(s):  
Binding Energy ◽  
Electric Field ◽  
External Electric Field ◽  
Stark Shift ◽  
Donor Impurity ◽  
Zinc Blende ◽  
Hydrogenic Donor Impurity ◽  
Donor Binding Energy ◽  
Quantum Well Wire ◽  
Hydrogenic Donor

The binding energy of a hydrogenic donor impurity in a zinc-blende GaN / AlGaN cylindrical quantum well wire (QWW) is calculated in the framework of effective-mass envelope-function theory using the plane wave basis. It is shown that the donor binding energy is highly dependent on the impurity position, the radius of the wire and the external electric field. In addition, Stark shift dependence on the radius of the QWW and the external electric field is also calculated. The donor binding energy has a maximum when the impurity is located at the center of the QWW. The donor binding energy decreases with the increase of the external electric field, but stark shift increases with the increase of the external electric field or the radius of the QWW.

An investigation on the effect of impurity position on the binding energy of quantum box under electric field with pressure and temperature

2018 ◽  
Vol 32 (13) ◽  
pp. 1850154
Author(s):  
S. Yilmaz ◽  
M. Kirak
Keyword(s):  
Hydrostatic Pressure ◽  
Binding Energy ◽  
Electric Field ◽  
Semiconductor Device ◽  
Donor Impurity ◽  
Energy Eigenvalues ◽  
Impurity Position ◽  
Mass Approximation ◽  
Field Temperature ◽  
Box Structure

In the present study, we have studied theoretically the influences of donor impurity position on the binding energy of a GaAs cubic quantum box structure. The binding energy is calculated as functions of the position of impurity, electric field, temperature and hydrostatic pressure. The variational method is employed to obtain the energy eigenvalues of the structure in the framework of the effective mass approximation. It has been found that the impurity positions with electric field, pressure and temperature have an important effect on the binding energy of structure considered. The results can be used to manufacture semiconductor device application by manipulating the binding energy with the impurity positions, electric field, pressure and temperature.

Sign in / Sign up

Export Citation Format

Share Document