Binding energy and polarizability in GaAs–(Ga,Al)As quantum-well wires

Hydrogenic impurities in graded GaAs–(Ga,Al)As quantum-well wires in an electric field

“…We conclude that, for quantum-well wires with large dimensions, the applied electric field produces an important effect on the electronic and optical properties, and in GQWWs, the changes in donor binding energy and polarizability being strongly dependent on the direction of the field. Our results qualitatively agree with other theoretical calculations [17]. We obtain, as a general feature, that for strong geometric confinements the binding energy is more influenced by the quantum confinement than by the applied electric field.…”

“…On the other hand, for the wider SQWW, L x ¼ 500 ( A, the variation is large especially for small electric field values. Qualitatively, we see that, these results give the same behavior as found by Duque et al We should point out, as expected, that our results are smaller than those of Duque et al [17], since we consider the finite potential confinements in the x-and zdirections. In their model the donor electron is confined in a quantum box.…”

“…The effect of an electric field, and the geometric form of the system on the binding energies of shallow-donor impurities in GaAs quantum-well wires was presented by several authors [14][15][16], considering an infinite confinement potential and using a variational scheme. Duque et al investigated the effect of an applied electric field on the binding energy, and polarizabilities of shallow-donor impurities implanted in rectangular cross-section GaAs-GaAlAs quantum-well wires [17], and in cylindrical GaAs low-dimensional systems [18]. They obtained, as a general feature, that the polarizability increases almost linearly for all applied electric fields, and the results qualitatively agree with other theoretical calculations [19][20][21][22].…”

“…2, we present the variation of the binding energy of a hydrogenic impurity as a function of the applied electric field for the SQWW and GQWW with different dimensions. In order to compare our results with that of Duque et al [17], we choose the dimensions L z ¼ 650 ( A, considering…”

Intense field effects on shallow donor impurities in graded quantum wells

“…Duque et al have investigated the effect of an applied electric field on the binding energy, and the polarizabilities of shallow-donor impurities implanted in rectangular crosssection GaAs-GaAlAs quantum well wires [19], and in cylindrical GaAs low-dimensional systems [20]. They observed, as a general feature, that the polarizability increases almost linearly for all applied electric fields.…”