Materials choice for ballistic transport: Group velocities and mean free paths calculated from realistic band structures

Abstract
We studied the effects of realistic band structures on the group velocities and mean free paths due to scattering by longitudinal optical phonons, ionized impurities, alloy disorder, and other electrons on limiting ballistic transport in GaAs, InAs, InP, GaInAs, GaAlAs, and InAsP alloys. The upper cutoff frequency and fraction of ballistic electrons transporting through devices made from these materials are calculated. For thick devices (≥500 Å), GaInAs alloys have distinct advantages. However, for thin devices (≊100 Å), the cutoff frequencies range around 15 THz, and none of the materials have an appreciably higher ballistic fraction than GaAs.