Effective g factor of 2D holes in strained Ge quantum wells

Abstract

The effective g-factor of 2D holes in modulation doped p-SiGe/Ge/SiGe structures was studied. The AC conductivity of samples with hole densities from 3.9 × 1011 to 6.2 × 1011 cm−2 was measured in perpendicular magnetic fields up to 8 T using a contactless acoustic method. From the analysis of the temperature dependence of conductivity oscillations, the g⊥-factor of each sample was determined. The g⊥-factor was found to be decreasing approximately linearly with hole density. This effect is attributed to the non-parabolicity of the valence band.