Investigation of LO phonon emission by hot holes and the effective mass for hole tunnelling in GaAs/(AlGa)As single barrier structures

Oscillatory structure in the low temperature current-voltage characteristics of Be-doped p-type GaAs/(AlGa)As/GaAs single barrier tunnelling devices is observed. The oscillations have a period Delta V=39 mV, close to h(cross) omega L /e, where h(cross) omega L is the LO phonon energy in GaAs. They result from energy relaxation of hot holes injected through the tunnel barrier. The sheet density in the hole accumulation layer adjacent to the tunnel barrier is obtained from the magneto-oscillations in I(V) for magnetic field B//J. This allows one to calculate the hole effective mass for tunnelling.