Exchange-induced band hybridization in InAs/GaSb based type II and broken-gap quantum well systems

Abstract

We demonstrate theoretically that the many-body effect such as exchange interaction can cause the hybridization of the electron and hole dispersion relations in InAs/GaSb based type II and broken-gap quantum well (QW) systems. As a result, a terahertz mini-gap at the anti-crossing points of the conduction and valence bands can be induced by the inter-layer electron–hole coupling via the Coulomb interaction. It is shown that the many-body effect is another important source of the hybridization of the dispersion relations in InAs/GaSb QW systems.