Study on transport properties of two-dimensional electron gases in n-Hg_0.80Mg_0.20Te interface accumulation layer

The transport properties in Hg_0.80Mg_0.20Te molecular beam epitaxy film has been studied in the temperature range from 1.5 to 250 K by variable magnetic-field Hall measurement. The experimental data have been analyzed using a hybrid approach consisting of the mobility spectrum (MS) technique followed by a multicarrier fitting (MCF) procedure. Both Shubnikov de Hass(SdH) Measurements and the hybrid approach show two-and three-dimensional electronic behaviors. Experimental results indicate that the two-dimensional electrons are due to an accumulation layer near the Hg_1-xMg_xTe-CdTe interface or the Hg_1-xMg_xTe-vacuum interface. Ionized impurity scattering of the three-dimension electron mobility dominates at low temperature (considering the screening effect) while lattice scattering dominates above 100 K. The scattering mechanism in Hg_1-xMg_xTe is very similar to that in Hg_1-xCd_xTe.