Pressure effect on the electron mobility in AlAs/GaAs quantum wells

By taking the influence of optical phonon modes into account, this paper adopts the dielectric continuum phonon model and force balance equation to investigate the electronic mobility parallel to the interfaces forAlAs/GaAs semiconductor quantum wells (QWs) under hydrostaticpressure. The scatteringfrom confined phonon modes, interface phonon modes and half-spacephonon modes are analysed and the dominant scattering mechanisms inwide and narrow QWs are presented. The temperature dependence of theelectronic mobility is also studied in the temperature range ofoptical phonon scattering being available. It is shown that theelectronic mobility reduces obviously as pressure increases from 0 to4GPa, the confined longitudinal optical (LO) phonon modes play animportant role in wide QWs, whereas the interface optical phonon modes are dominant innarrow QWs, the half-space LO phonon modes hardly influence the electronicmobility expect for very narrow QWs.