Temperature dependence of the mobility of two-dimensional hole systems in modulation-doped GaAs-(AlGa)As.

The temperature dependence of the mobility of two-dimensional hole systems at modulation-doped GaAs-(AlGa)As heterojunctions is determined. Its shape follows closely the equivalent curve for high-purity p-type bulk GaAs. Low-temperature mobilities beyond 4×104 cm2/Vs are found for areal hole densities of 5×1011 cm-2. The equivalent scattering times reach those of the best modulation-doped electron systems. In the temperature range where acoustic mode scattering prevails a T-3/4 dependence was observed. Studies under light illumination could not detect any persistent photoconductive effect in two-dimensional holes. [ABSTRACT FROM AUTHOR]