Electronic structure of diluted magnetic semiconductor superlattices: In-plane magnetic field effect

Abstract

The electronic structure of diluted magnetic semiconductor ͑DMS͒ superlattices under an in-plane magnetic field is studied within the framework of the effective-mass theory; the strain effect is also included in the calculation. The numerical results show that an increase of the in-plane magnetic field renders the DMS superlattice from the direct band-gap system to the indirect band-gap system, and spatially separates the electron and the hole by changing the type-I band alignment to a type-II band alignment. The optical transition probability changes from type I to type II and back to type I like at large magnetic field. This phenomenon arises from the interplay among the superlattice potential profile, the external magnetic field, and the sp-d exchange interaction between the carriers and the magnetic ions. The shear strain induces a strong coupling of the light-and heavy-hole states and a transition of the hole ground states from ''light''-hole to ''heavy''-holelike states.

Probing the low-temperature limit of the quantum anomalous Hall effect

“…This field-dependent feature highlights the pronounced splitting of the bulk valence band under high magnetic field in the thicker MTI samples (40). In general, magnetic dopants can induce an energy splitting between up and down spins, which has been well studied in diluted magnetic semiconductors (40,41). This splitting comes from the combined effect of the on-sight exchange energy and the Zeeman energy given by the applied field.…”

Ferromagnetism in High-Surface-Area ZnO Nanosheets Prepared by a Template-Assisted Hydrothermal Method

“…For the V O 's in the nearest neighbor, they can couple together by a ferromagnetic exchange interaction. [34,35] However, V O 's are not always located in the nearest neighbor. For the ones relatively far apart, the longer-range ferromagnetic exchange between them can be finished by mediation of polarized electrons.…”