DETERMINING BAND OFFSETS WITH TRIPLE QUANTUM-WELL STRUCTURES

Coupled triple quantum-well GaAs/AlGaAs heterostructures have been des igned to exhibit simultaneous electron and hole tunneling from the cen tral well to opposite side wells at a fixed applied bias. Band offset is the critical parameter for the design of structures with simultaneo us resonances. Photocurrent measurements reveal which triple quantum-w ell structures exhibit simultaneous resonances. A band offset ratio ne ar 62:38 is required to correctly engineer structures with simultaneou s resonances.