Spin-dependent resonant tunneling in double-barrier magnetic heterostructures

Abstract

Recent advances in molecular beam epitaxial growth made it possible to fabricate exotic heterostructures comprised of magnetic films or buried layers ${\mathrm{(ErAs,Ga}}_x{\mathrm{Mn}}_{\text{1−x}}\mathrm{As})$ integrated with conventional semiconductors (GaAs) and to explore quantum transport in these heterostructures. It is particularly interesting to study spin-dependent resonant tunneling in double-barrier resonant tunneling diodes (RTDs) with magnetic elements such as GaAs/AlAs/ErAs/AlAs/GaAs and ${\mathrm{GaAs/AlAs/Ga}}_{\mathrm{x}}{\mathrm{Mn}}_{\text{1−x}}$ As/AlAs/GaAs. We present the results of our theoretical studies and computer simulations of transmission coefficients and current-voltage characteristics of RTDs based on these double-barrier structures. In particular, resonant tunneling of holes in the ${\mathrm{Ga}}_x{\mathrm{Mn}}_{\text{1−x}}\mathrm{As-based}$ RTDs is considered. Our approach is based on ${k\cdot p}$ perturbation theory with exchange splitting effects taken into account.