Low magnification (a) bright-field STEM and (b)–(d) ADF STEM images of (Ga,Mn)As annealed at 903 K. The ADF inner detector semiangles used were (b) 78.4, (c) 47.4, and (d) 30.9 mrad. The viewing direction is close to the crystallographic [1-10] axis of the GaAs host.
High-resolution aberration-corrected (a), (b) TEM, (c) HAADF STEM, and (d) LAADF STEM images of cubic (Ga,Mn)As nanocrystals. The ADF detector inner semiangles used were (c) 78.4 and (d) 24.5 mrad.
Aberration-corrected high-resolution (a) TEM and (b) HAADF STEM images of two different hexagonal (Ga,Mn)As nanocrystals. The arrows indicate the positions of misfit dislocations. In (b) the inner detector semiangle used was 78.4 mrad.
(a), (c) Experimental and (b), (d) simulated electron diffraction patterns of (a), (b) cubic and (c), (d) hexagonal (Ga,Mn)As nanocrystals in GaAs. The viewing direction is [1-10] for GaAs.
(Color online) (a) LAADF (inner detector semiangle: 47.4 mrad) STEM image of a hexagonal (Ga,Mn)As nanocrystal. (b) LAADF intensity and Mn L edge EELS signal after background subtraction collected along the line marked in (a).
(Color online) Temperature dependence of the field-cooled magnetization for Ga0.995Mn0.005As annealed at 903 K recorded in a magnetic field of 4 kA/m (50 Oe). The inset shows a hysteresis loop acquired at T = 5 K (corrected by subtracting the diamagnetic contribution to the signal).
LAADF (inner detector semiangle: 47.4 mrad) STEM images recorded at specimen temperatures of (a) 773, (b) 823, (c) 848, and (d) 848 K; (d) was recorded 6 min after (c).
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