Polaron effects on the impurity binding energy in quantum wires

1995 ◽  
Vol 52 (7) ◽  
pp. 4662-4665 ◽  
Author(s):  
Francisco A. P. Osório ◽  
Marcos H. Degani ◽  
Oscar Hipólito
Keyword(s):  
Binding Energy ◽  
Quantum Wires

Variational Calculations of Donor Binding Energy in Rectangular Wurtzite Aluminium Gallium Nitride / Gallium Nitride Quantum Wires

2007 ◽  
Vol 1040 ◽  
Author(s):  
Choudhury Jayant Praharaj
Keyword(s):  
Gallium Nitride ◽  
Binding Energy ◽  
Electric Fields ◽  
Quantum Wire ◽  
Quantum Wires ◽  
Potential Profile ◽  
Nitride Semiconductors ◽  
Aluminium Gallium Nitride ◽  
Donor Binding Energy ◽  
Variational Calculations

AbstractWe present variational calculations of donor binding energy in rectangular wurtzite aluminium gallium nitride / gallium nitride quantum wires. We explicitly take into account the effect of spontaneous and piezoelectric polarization on the energy levels of donors in quantum wires. Wurtzite structure nitride semiconductors have spontaneous polarization even in the absence of externally applied electric fields. They also have large piezoelectric polarization when grown as pseudomorphic layers. The magnitude of both polarization components is of the order of 1013 electrons per cm2, and has a non-trivial effect on the potential profile seen by electrons. Due to the large built-in electric fields resulting from the polarization discontinuities at heterojunctions, the binding energies of donors is a strong function of the position inside the quantum wire. The potential profile in the 0001 direction can vary by as much as 1.5eV due to polarization effects for vertical dimensions of the quantum wire up to 20 angstroms. The probability density of electrons tends to concentrate near the minimum of the conduction band profile in the 0001 direction. Donors located close to this minimum tend to have a larger concentration of electron density compared to those located closer to the maximum. As a consequence, the binding energy of the former are higher compared to the latter. We use Lorentzian variational wavefunctions to calculate the binding energy as a function of donor position. The confinement potential enhances the binding by a factor of about 3 compared to donors in bulk nitride semiconductors, from about 30 meV to about 90 meV. The variation of binding energy with position is calculated to be more than 50% for typical compositions of the quantum wire regions. Our calculations will be useful for understanding device applications involving n-type doped nitride semiconductor quantum wires.

PHONON CONFINEMENT EFFECT ON THE BINDING ENERGY OF A HYDROGENIC IMPURITY IN QUANTUM WIRES IN THE ELECTRIC AND MAGNETIC FIELDS

2012 ◽  
Vol 15 ◽  
pp. 184-190
Author(s):  
ABBAS SHAHBANDARI
Keyword(s):  
Binding Energy ◽  
Magnetic Fields ◽  
Quantum Wires ◽  
Polar Optical Phonon ◽  
Phonon Confinement ◽  
Hydrogenic Impurity ◽  
Bound Polaron ◽  
Electric And Magnetic Fields ◽  
Applied Fields ◽  
Variation Technique

The effect of phonon confinement on ground state binding energy of bound polaron in polar quantum wires with a finite confining potential investigated by Landau-Pekar variation technique. The effect of external electric and magnetic fields is taken into account as well. The obtained results show that the polar optical phonon confinement leads to a considerable enhancement of the polaron effect and these corrections increase with increasing of applied fields.

BARRIER THICKNESS DEPENDENCE OF OPTICAL ABSORPTION OF EXCITONS IN GaAs COUPLED QUANTUM WIRE

2004 ◽  
Vol 11 (01) ◽  
pp. 49-55 ◽  
Author(s):  
E. KASAPOGLU ◽  
M. GUNES ◽  
H. SARI ◽  
I. SÖKMEN
Keyword(s):  
Binding Energy ◽  
Optical Absorption ◽  
Quantum Wire ◽  
Variational Approach ◽  
Quantum Wires ◽  
Binding Energies ◽  
Barrier Thickness ◽  
Mass Approximation ◽  
Quantum Well Wires ◽  
Coupled Quantum Well

We have calculated the binding energy of excitons, and the interband optical absorption in rectangular coupled quantum-well wires of GaAs surrounded by Ga 1-x Al x As in effective-mass approximation, using the variational approach. Results obtained show that the exciton binding energies and optical absorption depend on the sizes of the wire and barrier thickness. To the best of our knowledge the exciton binding energy and interband optical absorption in the rectangular coupled quantum wires have not been clarified yet.

HEAVILY DOPED HARMONIC CONFINED QUANTUM WIRES

1992 ◽  
Vol 06 (29) ◽  
pp. 1881-1885
Author(s):  
I.C. DA CUNHA LIMA ◽  
A. FERREIRA DA SILVA
Keyword(s):  
Binding Energy ◽  
Quantum Well ◽  
Density Of States ◽  
Gate Voltage ◽  
Quantum Wires ◽  
Impurity Band ◽  
Semiconductor Heterostructures ◽  
One Dimensional ◽  
Impurity Density ◽  
Heavily Doped

Quasi-one-dimensional channels have already been fabricated by holographic lithography on semiconductor heterostructures. We study the formation of an impurity band for shallow donors located inside the channels assuming they have been created by applying a modulated gate voltage in a quantum well of AlxGa1−xAs−GaAs. We calculate the changes in the impurity density of states as a function of the gate voltage. It is shown that the increase of the applied gate voltage leads to higher binding energy and larger impurity bandwidth.

Biexciton Binding Energy in ZnSe Quantum Wells and Quantum Wires

2002 ◽  
Vol 231 (1) ◽  
pp. 11-18 ◽  
Author(s):  
H.P. Wagner ◽  
H.-P. Tranitz ◽  
W. Langbein ◽  
J.M. Hvam ◽  
G. Bacher ◽  
...  
Keyword(s):  
Binding Energy ◽  
Quantum Wells ◽  
Quantum Wires ◽  
Biexciton Binding Energy

scholarly journals Exciton Binding Energy in GaAs V-Shaped Quantum Wires

1994 ◽  
Vol 73 (21) ◽  
pp. 2899-2902 ◽  
Author(s):  
R. Rinaldi ◽  
R. Cingolani ◽  
M. Lepore ◽  
M. Ferrara ◽  
I. M. Catalano ◽  
...  
Keyword(s):  
Binding Energy ◽  
Quantum Wires ◽  
Exciton Binding Energy
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