Control of the residual doping of InAs/(GaIn)Sb infrared superlattices

Magnetotransport and photoluminescence (PL) measurements on InAs/(Galn)Sb superlattices (SLs) .grown by molecular-beam epitaxy on GaSb substrates at different substrate temperatures are reported. With increasing growth temperature, a transition of the SLs from residual n-type to residual p-type doping was observed. For n-type samples, a decrease in the electron concentration leads to a strong increase in the PL intensity. In contrast, the PL intensity of p-type samples is only weakly dependent on the hole concentration. This correlation can be used to control the residual doping of the SLs.