(Color online) Magnetization measured during cooling under constant field applied along the  direction: (a) Ga0.97Mn0.03As/GaAs (A4: d M = 24.4 ML, d N = 25.1 ML, and d SL = 49.5 ML) (c) Ga0.97Mn0.03As/GaAs (A3: d M = 24.4 ML, d N = 12.4 ML, and d SL = 36.8 ML) and (e) Ga0.97Mn0.03As/GaAs:Be (B3: d M = 24.4 ML, d N = 12.4 ML, and d SL = 36.8 ML). The right panels show the field dependence of the magnetization obtained by interpolating the magnetization data shown in the left. The lines are guides to the eye.
(Color online) M vs μ 0 H hysteresis loops of the A4 (Ga0.97Mn0.03As/GaAs, d M = 24.4 ML, d N = 25.1 ML, and d SL = 49.5 ML) SL sample. The thick red lines indicate the initial magnetization after zero-field cooling. The inset in (d) shows the hysteresis loop near zero field.
(Color online) The temperature dependence of the saturation magnetization (μ 0 H = 100 mT; closed circles) and the remnant magnetization (μ 0 H = 0 mT; open squares) for (a) A4, (b) A3, and (c) B3.
(Color online) Description of the directions of the cooling field (dashed arrows, μ 0 HC ), guide field (solid arrow, μ 0 HG ), and the lattice orientations in the polarized neutron reflectivity measurements. The double-ended circles represent constant-energy surfaces of the uniaxial anisotropy. The thin arrows indicate either (a) FM, or (b) AFM spin arrangements between magnetic layers.
(Color online) Polarized neutron reflectivity of the GaMnAs/GaAs (A4) SL sample measured at 6 K. The data are vertically shifted for clarity. HC and HG denote the cooling field and the guide field, respectively. Solid lines are the full dynamical calculations using the reflpak program (see Ref. 32) for SL magnetization alignments as illustrated in the middle of (b). In panel (b), only the data measured at μ 0 HG (|| ) = 1.4 mT are shown.
Article metrics loading...
Full text loading...