EFFECT OF MAGNETIC FIELDS ON BINDING ENERGY OF IMPURITY STATES IN A SEMIMAGNETIC PARABOLIC QUANTUM DOT

2007 ◽  
Vol 21 (17) ◽  
pp. 3035-3044 ◽  
Author(s):  
A. JOHN PETER
Keyword(s):  
Magnetic Field ◽  
Binding Energy ◽  
Quantum Dot ◽  
Mean Field Theory ◽  
Mean Field ◽  
Realistic Model ◽  
Mass Approximation ◽  
Maximum Value ◽  
The Magnetic Field ◽  
Parabolic Quantum Dot

Using a variational approach, the binding energy of shallow hydrogenic impurities in a semimagnetic parabolic quantum dot is calculated within the effective mass approximation. The binding energy is computed for Cd 1-x in Mn x in Te / Cd 1-x out Mn x out Te structures as a function of the dot size in an external magnetic field. The results show that the impurity binding energy (i) increases with the reduction in dot sizes (ii) decreases when the magnetic field is increased for a given dot and (iii) increases to a maximum value at 100 Å and then decreases as the size of the dot increases beyond 100 Å for a realistic model. Spin polaronic shifts are estimated using a mean field theory. These results are compared with the existing literatures.

SHAPE EFFECT OF SEMIMAGNETIC QUANTUM DOT ON THE BOUND MAGNETIC POLARON

2011 ◽  
Vol 10 (04n05) ◽  
pp. 665-668 ◽  
Author(s):  
A. MERWYN JASPER DE REUBEN ◽  
K. JAYAKUMAR
Keyword(s):  
Magnetic Field ◽  
Variational Principle ◽  
Binding Energy ◽  
Quantum Dot ◽  
Effective Mass ◽  
Shape Effect ◽  
Magnetic Polaron ◽  
Bound Magnetic Polaron ◽  
Mass Approximation ◽  
The Magnetic Field

The effect of geometry, concentration of Mn ion and the magnetic field on the binding energy of a donor and the donor bound magnetic polaronic shift in a finite Cd 1–x1 Mn x1 Te / Cd 1–x2 Mn x2 Te Quantum Dot within the effective mass approximation is carried out employing the variational principle. The results are presented and discussed.

EFFECTS OF MAGNETIC AND ELECTRIC FIELDS ON THE HYDROGENIC IMPURITY IN AN ELLIPSOIDAL PARABOLIC QUANTUM DOT

2008 ◽  
Vol 15 (03) ◽  
pp. 201-205 ◽  
Author(s):  
E. KASAPOGLU ◽  
H. SARI ◽  
I. SOKMEN
Keyword(s):  
Binding Energy ◽  
Quantum Dot ◽  
Electric Fields ◽  
Magnetic Field Dependence ◽  
Hydrogenic Impurity ◽  
Mass Approximation ◽  
Donor Binding Energy ◽  
Potential Case ◽  
The Magnetic Field ◽  
Parabolic Quantum Dot

The binding energy of a hydrogen-like impurity in an ellipsoidal parabolic quantum dot under the magnetic and electric fields have been discussed by using the effective mass approximation and the variational method. We have calculated the effects of the magnetic and electric fields on the binding energy of donor impurities in the quantum dots with different confinement potentials. We conclude that the structural confinement is very effective, and especially in the weak confinement potential case the magnetic field dependence of the donor binding energy is more pronounced.

THE EFFECT OF POSITION DEPENDENT EFFECTIVE MASS OF HYDROGENIC IMPURITIES IN PARABOLIC GaAs/GaAlAs QUANTUM DOTS IN A STRONG MAGNETIC FIELD

2009 ◽  
Vol 23 (26) ◽  
pp. 5109-5118 ◽  
Author(s):  
A. JOHN PETER
Keyword(s):  
Magnetic Field ◽  
Quantum Dots ◽  
Binding Energy ◽  
Effective Mass ◽  
Bound States ◽  
Mass Approximation ◽  
Infinite Case ◽  
Dependent Mass ◽  
The Magnetic Field ◽  
Peak Value

The binding energy of shallow hydrogenic impurities in parabolic GaAs/GaAlAs quantum dots is calculated as a function of dot radius in the influence of magnetic field. The binding energy has been calculated following a variational procedure within the effective-mass approximation. Calculations are presented with constant effective-mass and position dependent effective masses. A finite confining potential well with depth is determined by the discontinuity of the band gap in the quantum dot and the cladding. The results show that the impurity binding energy (i) increases as the dot radius decreases for the infinite case, (ii) reaches a peak value around 1R* as the dot radius decreases and then diminishes to a limiting value corresponding to the radius for which there are no bound states in the well for the infinite case, and (iii) increases with the magnetic field. Also it is found that (i) the use of constant effective mass (0.067 m0) is justified for dot sizes ≥ a* where a* is the effective Bohr radius which is about 100 Å for GaAs , in the estimation of ionization energy and (ii) the binding energy shows complicated behavior when the position dependent mass is included for the dot size ≤ a*. These results are compared with the available existing literatures.

THE INTERSUBBAND TRANSITIONS AND BINDING ENERGY OF SHALLOW DONOR IMPURITIES IN DIFFERENT SHAPED QUANTUM WELLS UNDER THE MAGNETIC FIELD

2011 ◽  
Vol 25 (32) ◽  
pp. 2451-2459 ◽  
Author(s):  
U. YESILGUL ◽  
F. UNGAN ◽  
E. KASAPOGLU ◽  
H. SARI ◽  
I. SÖKMEN
Keyword(s):  
Magnetic Field ◽  
Binding Energy ◽  
Field Strength ◽  
Variational Method ◽  
Quantum Wells ◽  
Shallow Donor ◽  
Intersubband Transitions ◽  
Mass Approximation ◽  
Semiconductor Quantum Wells ◽  
The Magnetic Field

The intersubband transitions and impurity binding energy in differently shaped semiconductor quantum wells under a magnetic field are calculated using a variational method within the effective mass approximation. Our calculations have revealed the dependence of the intersubband transitions and impurity binding energy on the magnetic field strength and the shape of the quantum wells.

GROUND STATE ENERGIES OF HYDROGEN-LIKE IMPURITY IN A LENS-SHAPED QD

2004 ◽  
Vol 18 (17n19) ◽  
pp. 2529-2533 ◽  
Author(s):  
XIANGHUA ZENG ◽  
JIAFENG CHANG ◽  
PENGXIA ZHOU
Keyword(s):  
Magnetic Field ◽  
Quantum Dot ◽  
Ground State Energy ◽  
Ground State ◽  
State Energy ◽  
Lateral Deviation ◽  
Mass Approximation ◽  
The Magnetic Field ◽  
Ground State Energies ◽  
Electronic Ground

In this paper,the ground state energies of hydrogen-like impurity in a lens-shaped quantum dot ( GaAs / In 1-x Ga x As ) under vertical magnetic field have been discussed by using effective mass approximation and variational method. It gives that for a lens-shaped quantum dot, due to the asymmetry of the vertical and lateral bound potentials, the electronic ground state energies are related not only with the deviation distance but also with the deviation direction; for the spherical quantum dot, the ground state energy is only related with the distance of the impurity deviation, neither with vertical nor lateral deviation. And with the increasing of the magnetic field, the ground state energy is increasing.

THE EFFECTIVE MASS OF STRONG-COUPLING MAGNETOPOLARONS IN A PARABOLIC QUANTUM DOT

2011 ◽  
Vol 25 (32) ◽  
pp. 2419-2425 ◽  
Author(s):  
SHI-HUA CHEN ◽  
QING-ZHOU YAO
Keyword(s):  
Magnetic Field ◽  
Quantum Dot ◽  
Field Strength ◽  
Effective Mass ◽  
Magnetic Field Strength ◽  
Strong Coupling ◽  
Function Approximation ◽  
Gaussian Function ◽  
The Magnetic Field ◽  
Parabolic Quantum Dot

Within the framework of the Landau–Pekar variational method we have investigated the effective mass of strong-coupling magnetopolarons in a parabolic quantum dot. The effective mass as functions of the magnetic field strength and the confinement length of the quantum dot are obtained in the Gaussian function approximation. It is shown that the effective mass increases with the increasing magnetic field strength and increases with the decrease in the size of the quantum dot (QD).

BINDING ENERGY OF ACCEPTORS IN SEMIMAGNETIC QUANTUM DOTS

2006 ◽  
Vol 05 (01) ◽  
pp. 173-181 ◽  
Author(s):  
A. JOHN PETER
Keyword(s):  
Quantum Dots ◽  
Binding Energy ◽  
Bound States ◽  
Mean Field Theory ◽  
Mean Field ◽  
Binding Energies ◽  
Mass Approximation ◽  
Variational Calculations ◽  
Shallow Acceptors ◽  
Peak Value

The binding energies of shallow acceptors in Cd 1-x in Mn x in Te/ Cd 1-x out Mn x out Te quantum dots are calculated in the presence of external magnetic fields. Variational calculations are performed within effective mass approximation. The results show that the impurity binding energy (i) increases with the reduction in dot sizes, (ii) decreases with the magnetic field is increased for a given dot, and (iii) reaches a peak value as the dot radius decreases and then diminishes to a limiting value corresponding to the radius for which there are no bound states in the quantum dot. Spin polaronic shifts are estimated with the acceptor envelope function using a mean field theory. These results are compared with the existing literatures.

EXCITON STATES AND INTERBAND TRANSITIONS IN THE DIRECT-GAP Ge/SiGe QUANTUM DOT

2010 ◽  
Vol 24 (12) ◽  
pp. 1191-1197 ◽  
Author(s):  
CONGXIN XIA ◽  
YAMING LIU ◽  
SHUYI WEI
Keyword(s):  
Binding Energy ◽  
Quantum Dot ◽  
Ground State ◽  
Exciton Binding Energy ◽  
Emission Wavelength ◽  
Long Wavelength ◽  
Mass Approximation ◽  
Quantum Size ◽  
Maximum Value ◽  
Sige Quantum Dot

The ground-state exciton binding energy and interband emission wavelength in the direct-gap Ge / SiGe quantum dot (QD) are investigated by means of a variational approach, within the framework of effective-mass approximation. Numerical results show that the ground-state exciton binding energy has a maximum value with increasing quantum size of the direct-gap Ge / SiGe QD. The interband emission wavelength is increased when the QD size is increased. Our results indicate the direct-gap Ge / SiGe QD can be applied for long wavelength optoelectronic devices.

Sign in / Sign up

Export Citation Format

Share Document