Exchange-mediated anisotropy of (ga,mn)as valence-band probed by resonant tunneling spectroscopy.
We report on experiments and theory of resonant tunneling anisotropic magnetoresistance (TAMR) in AlAs/GaAs/AlAs quantum wells (QW) contacted by a (Ga,Mn)As ferromagnetic electrode. Such resonance effects manifest themselves by bias-dependent oscillations of the TAMR signal correlated to the successive positions of heavy (HH) and light (LH) quantized hole energy levels in GaAs QW. We have modeled the experimental data by calculating the spin-dependent resonant tunneling transmission in the frame of the 6 x 6 valence-band k.p theory. The calculations emphasize the opposite contributions of the (Ga,Mn)As HH and LH subbands near the Gamma point, unraveling the anatomy of the diluted magnetic semiconductor valence band.
Elsen
M
M
Unité Mixte de Physique CNRS-Thales, Route Départementale 128, 91767 Palaiseau Cedex and Université Paris-Sud 91405, Orsay, France.
Jaffrès
H
H
Mattana
R
R
Tran
M
M
George
J-M
JM
Miard
A
A
Lemaître
A
A