Two‐dimensional semimetal channel in a type II broken‐gap GaInAsSb/InAs single heterojunction

High magnetic field magnetoresistance and quantum Hall effect (QHE) in type II broken-gap Ga 1-x In x Sb 1-y As y /p-InAs single heterostructures based on undoped or doped with Zn and Te quaternary epilayers have been investigated to determine the effect of the carrier concentration and doping type on the 2D-electron density and quantum conductivity. The two-dimensional nature of quantum oscillations was established from the angular dependence of Shubnikov-de Haas (SdH) oscillations and observation of the QHE plateaus in the Hall conductivity in high magnetic fields when the upper electronic sub-bands become empty. We have observed maxima of σ xy (H) between the quantised Hall states at the filling factors v= 1, 2, and 3. The QHE plateau-to-plateau transitions from v= 3 to v= 2 and from v= 2 to v= 1 were different from the ones corresponding to one-type carrier. Doping of the epilayer alters the band bending for holes and electrons at the heteroboundary and results in changes of the electron concentration and SdH period according to the filling of the multi sub-band structure for the electron channel.