Channel sensitivity to gate roughness in a splitgate GaAsAlGaAs heterostructure Appl.

No abstract

Ballistic transport of hot electrons was used to characterize the relevant transport lengths in the twodimensional electron gas formed in an In 0.53 Ga 0.47 As/In 0.76 Ga 0.24 As/InP heterostructure. This method allows a distinction between impurity scattering, alloy scattering, and electron-electron scattering. Using adjacent point contacts separated by only a few hundred nanometers, we determine the ballistic mean free path for cold electrons to be approximately L bal ϭ970 nm. Fitting the electron excess energy-dependent peak height of the focusing maxima, good agreement can be obtained by including the energy dependence of ionized impurity scattering. The mean distance between impurities L imp is determined to be approximately 1.2 m and the alloy scattering length L alloy is 4.5 m.