Pressure-induced elimination of the hole gas in semimetallic GaSb-InAs-GaSb heterostructures

We report low-temperature magnetotransport measurements under hydrostatic pressure (up to 1.2 GPa) on a GaSb-InAs-GaSb double heterostructure. At ambient pressure the sample shows mixed conduction by electrons and holes. Pressure induces a decrease in the carrier concentrations which leads to a semimetal-semiconductor transition. In the semiconductor regime, xx(B) and xy(B) curves show the normal behavior expected for one-carrier two-dimensional conduction, while in the semimetallic case this behavior is altered by the partial compensation of the system.