Effects of phonon confinement on high-electric field electron transport in an InGaAs/InAlAs quantum well with an inserted InAs barrier

The alternating change of electron mobility values in the modulation doped InAlAs/InGaAs/InAlAs quantum well (QW) dependently on a thickness of the InAs layer inserted in the center of the QW is theoretically predicted and experimentally observed. The electron mobility enhancement by a factor of 1.5–2 takes place when the 4 nm-thick InAs layer is inserted into the 17 nm-width QW. The experimental maximal value of the electron drift velocity at the threshold electric field for intervalley electron scattering achieves (1.8−2)×107 cm/s and does not nearly depend on the thickness of the InAs insert. The high value of maximal drift velocity is conserved at the additional doping of the InAs insert up to electron density of 4×1012 cm−2 in the QW.