Resonant tunneling magnetoresistance in MnAs/III-V/MnAs junctions

Vincent Garcia (1) , H Jaffres , M Eddrief (1) , M Marangolo (1) , Victor H. Etgens (1) , Jm George

1 INSP - Institut des Nanosciences de Paris

This paper investigates the magnetoresistance of micron-sized MnAs/GaAs(AlAs)/MnAs magnetic tunnel junctions. We measure an asymmetric bias dependence of the magnetoresistance in which the negative contribution is attributed to resonant tunneling through a midgap defect band. Within this model we find a spin polarization of 60% for MnAs at the interface with GaAs. Moreover, we show that spin-dependent tunneling is a powerful technique for spectroscopic measurements of defects in a very thin layer.

Domaines: Matière Condensée [cond-mat]

Vincent Garcia, H Jaffres, M Eddrief, M Marangolo, Victor H. Etgens, et al.. Resonant tunneling magnetoresistance in MnAs/III-V/MnAs junctions. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2005, 72 (8), pp.081303. ⟨10.1103/PhysRevB.72.081303⟩. ⟨hal-01293059⟩