Carrier capture into a GaAs quantum well with a separate confinement region:: comment on quantum and classical aspects

We study the optic-phonon-mediated carrier capture in a narrow GaAs quantum well with a 100 nm separate confinement region. In a standard quantum model capture means the carrier scattering from the energy subband above the quantum well into a subband in the quantum well. We use the quantum model in parallel with a classical model in which a classical carrier is captured during collisionless motion when emitting the optic phonon inside the GaAs layer. Comparison with the experiment of Blom et at (1993 Phys. Rev. B 47 2072) suggests that the quantum capture model is valid not only for electrons but also for heavy holes in the case of very narrow (2.6 nm) quantum wells. In the case of wider quantum wells the available experimental data support equally the quantum as well as classical hole capture models and do not allow us to draw a definite conclusion. Finally, the effect of the phonon confinement on the quantum capture is evaluated and discussed.