PRESSURE INVESTIGATION OF THE QUANTUM HALL-EFFECT IN INTRINSIC SEMIMETALLIC INAS (GA,IN)SB HETEROSTRUCTURES/

We have performed magnetotransport measurements on InAs/(Ga,In)Sb hete rostructures under hydrostatic pressure. The system has a cross gap ba nd alignment which leads to the formation of co-existent 2D electron-h ole gases. The amount of overlap and thus the electron and hole concen trations can be tuned by the application of hydrostatic pressure. The samples studied here have nearly equal electron and hole concentration s and show large oscillatory quantum Hall features. Measurements of th e band overlap Delta and its rate of change with pressure d(Delta)/dP provides evidence that both the growth direction and also the composit ion of the interface layer play an important role in determining the b and line-up.