Impurity scattering with semiclassical screening in multiband quasi-one-dimensional systems

We present a calculation of screened impurity scattering in multiband GaAs one-dimensional systems. The influence of background impurities is extended to a domain outside the wire within a phenomenological model. Screening effects are evaluated in the semiclassical Thomas-Fermi approximation. A feature of our model is the consideration of level degeneracy which enhances carrier occupation and screening in higher subbands. For confinement conditions corresponding to subband separation equal to the thermal energy, we found that this effect equalizes the different scattering rates in each subband.