Donor binding energies in GaAs quantum wells considering the band nonparabolicity effects and the wavefunction elongation

2000-09-01
Aktas, S
Okan, SE
Erdogan, I
Akbas, H
Tomak, Mehmet
The donor binding energies in finite GaAs/GaxAl1-As-x quantum wells have been calculated by considering the confinement of electrons, which increases as the well width increases. The variational solutions have been improved by using a two-parameter trial wavefunction, and by including the conduction band nonparabolicity. It is shown that the method used gives results in agreement with those obtained in the experiments on the effective mass and the donor binding energy, both of which are strongly dependent on the well width. (C) 2000 Academic Press.
SUPERLATTICES AND MICROSTRUCTURES

Suggestions

Binding energies of helium-like impurities in parabolic quantum wells under an applied electric field
Okan, SE; Akbas, H; Aktas, S; Tomak, Mehmet (Elsevier BV, 2000-09-01)
We present a variational method to compute the binding energies of helium-like impurities in finite parabolic GaAs-Ga1-xAlxAs quantum wells. The effects of band nonparabolicity in the conduction band are taken into account within the effective mass approximation. The dependence of the impurity binding energy on the applied electric field and the impurity position is also discussed together with the polarization effect for all cases. (C) 2000 Academic Press.
Screening effect on the binding energies of shallow donors, acceptors and excitons in finite-barrier quantum wells
Akbas, H; Aktas, S; Okan, SE; Ulas, M; Tomak, Mehmet (Elsevier BV, 1998-01-01)
The conduction and valence subband energies in the presence of an electric field are calculated using the fifth-order Runge-Kutta method. The binding energies of shallow donors, accepters and excitons in finite-barrier GaAs/Ga1-xAlx As quantum wells are then obtained variationally in the presence of a magnetic field. The effects of a spatially dependent screening function epsilon(r) On the calculation of binding energies are specifically investigated. The use of epsilon(r) in comparison with the use of a co...
Subband structure and excitonic binding of graded GaAs/Ga1-xAlxAs quantum wells under an electric field
Sari, H; Ergun, Y; Elagoz, S; Kasapoglu, E; Sokmen, I; Tomak, Mehmet (Elsevier BV, 1998-01-01)
The effects of an applied electric field on subband energies and excitonic binding for a graded GaAlAs quantum well are calculated variationally within the effective mass approximation. The very sensitive dependence of subband energies on the applied field is calculated using a model potential profile and exact electron and hole wavefunctions. Our calculations have revealed the dependence of the energy shifts of subbands, and excitonic binding on the field direction in the graded quantum well. This permits ...
The electronic structure of a quantum well under an applied electric field
Sari, H; Ergun, Y; Sokmen, I; Tomak, Mehmet (Elsevier BV, 1996-01-01)
The effects of an applied electric field on quantum well subband energies are calculated variationally within the effective mass approximation for model potential profiles. The concept of a quasi-bound state is examined critically. For higher electric field values it is shown that the quasi-bound state approximation for the ground and first excited state of the electron, and for the ground state of the hole is valid. (C) 1996 Academic Press Limited
Electron-phonon short-range interactions mobility and p- to n-type conversion in TlGaS2 crystals
Qasrawi, AF; Hasanlı, Nızamı (Wiley, 2006-02-01)
The conductivity type conversion from p- to n-type at a critical temperature of 315 K in TlGaS2 crystals is observed through the Hall effect measurements in the temperature range of 200-350 K. The analysis of the temperature-dependent electrical resistivity, Hall coefficient and carrier concentration data reveals the extrinsic type of conduction with donor impurity levels that behave as acceptor levels when are empty. The data analysis allowed the calculation of hole and electron effective masses of 0.36m(0...
Citation Formats
S. Aktas, S. Okan, I. Erdogan, H. Akbas, and M. Tomak, “Donor binding energies in GaAs quantum wells considering the band nonparabolicity effects and the wavefunction elongation,” SUPERLATTICES AND MICROSTRUCTURES, pp. 165–169, 2000, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/40711.