Pressure dependent two-dimensional electron transport in defect doped InGaAs/InP heterostructures

We have measured the transport properties of InGaAs/InP heterostructures where donor-like native defects incorporated in a low temperature grown InP barrier are used as a source of electrons. Conductance of such structures shows comparable contributions from low mobility electrons in the InP barrier and from the two-dimensional electron gas (2DEG) at the heterostructure interface. We used high hydrostatic pressure to eliminate the low mobility conductance and were able to determine the parameters of two-dimensional electron gas. We find that the highest two-dimensional electron mobility of 3 × 10⁴ cm²/Vs is determined by the scattering from the background ionized impurities located in the InGaAs quantum well.