Γ-Xmixing in GaAs/AlxGa1−

Hydrostatic pressure effects on the donor impurity‐related photoionization cross‐section in cylindrical‐shaped GaAs/GaAlAs quantum well wires

“…In agreement with previous experimental work [14,15] it is clear that the potential that confines the electrons in the whole range of the applied pressures is essentially given by the difference between the energy associated with the Γ point in the conduction band for the barrier material and the well material. However, the Γ-X crossing in the barrier material for pressure values close to 13.5 kbar generates an interference in the height of the potential well, and as a consequence there is a deviation of the linear behavior for the hydrostatic pressure of the photoluminescence spectra (see, for example, the highpressure range in Fig.…”

“…[14]). Burnett et al [15] have calculated the confined electron states in single and double GaAs/GaAlAs quantum wells including the Γ-X mixing in the two-band Hamiltonian for electrons in order to describe the non-linear behavior with pressure in the photoluminescence spectra. In the present work we follow the Elabsy model [4] for the potential barrier that confines the electrons in the QD and in the QWW.…”

Effects of hydrostatic pressure on the conduction‐electron g ‐factor in GaAs–Ga1–xAlx As quantum wells

“…We point out that the effect of the hydrostatic pressure is to diminish the energy of the Landau levels, as expected due to the decrease of the confining potential as the pressure applied over the system is increased [7,10,12]. The applied magnetic field breaks up the spin degeneracy, and pressure effects may lead to changes in the g-factor sign [see Fig.…”

“…Therefore, the electron effective g-factor is a very important parameter for a number of applications based on magneto-optical and magnetotransport studies of semiconductor heterostructures, and a great amount of experimental and theoretical work has been devoted to the understanding of its properties in low-dimensional semiconductor systems [2][3][4][5]. In addition, in GaAs-Ga 1-x Al x As quantum wells (QWs), for example, it is well known that the application of hydrostatic pressure modifies the electron band structure leading to changes in the electron and hole energy states and causing both direct and indirect electron-hole transitions [6,7]. Such effects may show up in the electron-effective g-factor, and may be used to tune the electron spin dynamics and relaxation in semiconductor heterostructures.…”

Hydrostatic pressure, electric and magnetic field effects on shallow donor impurity states and photoionization cross section in cylindrical GaAs–Ga1–xAlx As quantum dots

“…The hydrostatic pressure effects on the electronic and impurity states in low-dimensional heterostructures such as quantum wells (QW), quantum well-wires (QWW), and quantum dots (QD) is an important subject due to its potential applications in optoelectronic and terahertz devices and many theoretical and experimental works have been made in order to shed light into its possible uses [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. As a general feature, the experimental and theoretical findings show that the binding energy for shallow-donor impurities and excitonic complexes increases with increasing applied hydrostatic pressure for essentially all low-dimensional heterostructures.…”