Subband population and electron subband mobility for two interacting Si-δ-doping layers in GaAs

In this paper we present measurements of the subband population and quantum mobility in the various subbands of GaAs samples that contain two coupled Si-δ-layers and of GaAs samples that contain a single δ-doping layer which was increased in thickness by thermal annealing. The measured subband population will be compared with the subband population obtained from self-consistent solutions of the coupled Poisson and Schrödinger equation. The experimental results on both types of structures are compared and show that the population of the higher subbands is not sensitive to the charge distribution of the ionized donors in the center of the confining potential. The quantum mobility in the highest subbands on the contrary is sensitive to the distribution of the ionized donors