Observation of pronounced effect of compressive strain on room-temperature transport properties of two-dimensional hole gas in a strained Ge quantum well

Strong effect of compressive strain on room-temperature transport properties of two-dimensional hole gas (2DHG) confined in a strained Ge quantum well (QW) of SiGe heterostructures was observed. By increasing compressive strain in the Ge QW the pronounced increase of 2DHG gas density and conductivity were obtained in the full range of researched strain variation. At the same time the increase of 2DHG drift mobility was observed until a certain high strain in the Ge QW, but showed slight reduction under higher strain. Nevertheless the monotonous enhancement of 2DHG conductivity was observed.