Hot electron ballistic transport in small four-terminal n-algaas/ingaas/gaas structures

We have studied hot electron ballistic transport in small four-terminal structures fabricated by Ga focused- ion-beam implantation from AlGaAs/InGaAs/GaAs modulation doped material. We have determined the characteristics of negative bend resistance as a function of hot electron energy by analyzing the magneto-resistance data. We have found that the ballistic nature of hot electrons is progressively lost when the excess energy of hot electrons exceeds LO-phonon energy, although the effect is smaller than in structures fabricated from conventional AlGaAs/GaAs modulation doped material due to the difference in the electron-phonon coupling strength. We have also found that the collimation effect, which is related to the geometry of the electron emitter, is preserved for hot ballistic electrons.