Magnetotransport and electron subband studies of edge delta-doped Al _0.27Ga_0.73As/GaAs single quantum wells

Shubnikov-de Haas and Van der Pauw Hall effect measurements at 1.5 K have been carried out to investigate the existence of a two-dimensional electron gas and to determine subband energies in a Si-delta-doped Al_0.27Ga _0.73As/GaAs single quantum well. The fast Fourier transformation results for the S-dH data indicate clearly the occupation of two subbands in edge delta-doped Al_0.27Ga_0.73As/GaAs quantum wells. Capacitance-voltage profiling and temperature-dependent photoluminescence measurements have been performed to characterize the properties of edge delta-doped Al_0.27Ga_0.73As/GaAs quantum wells. Using these experimental results and a self-consistent numerical method which took into account the exchange-correlation effects, the electron subband energies were determined. These results indicate that edge delta-doped Al _0.27Ga_0.73As/GaAs single quantum wells are similar to the asymmetrical potential wells occupied by relatively high electron carrier densities.