Full text loading...
(a) High-angle annular dark-field TEM image of a 15 period (001)-oriented DFH with structure . (b) X-ray reflectivity data from a 30 period (001)-oriented DFH with structure showing a feature at arising from the density contrast between Mn rich and deficient regions within each period. The superlattice periodicity is 22.3 Å, given by , in good agreement with the expected structure. The solid line shows a fit using software that employs Parratt’s formalism for dynamical scattering. The broad features between and are due to the native surface oxide.
(a) Magnetization vs temperature for DFHs with structure grown on (201) substrate orientation along different measuring field directions. (b) Magnetization vs temperature for DFHs with structure and different substrate orientations: (001), , (201), and (110). (c) as a function of spacer thickness ( ML) for DFH samples with structure on different substrate orientations. Symbols correspond to substrate orientations shown in the legend in panel (b). (d) Variation in with hole density (300 K) in DFH samples with varying substrate orientation and spacer thickness. Symbols correspond to substrate orientations shown in the legend in panel (b).
(a) Magnetization vs temperature for random alloy samples grown on different substrate orientations. (b) Variation in with estimated hole density (300 K) for random alloy samples with different substrate orientations. Green circles are random alloys with nominal Mn compositions of and blue squares for . In each case, increasing follows the substrate orientation order: (110), (201), , and (001). (c) SIMS analysis of depth dependent Mn concentration in random alloy samples with different substrate orientations showing identical Mn incorporation. The increased Mn concentration near the sample surface may be the result of unintentional annealing. (d) Effect of annealing on showing that difference in Mn interstitial densities between orientations is unlikely. The annealing is carried out at in nitrogen atmosphere. Symbols correspond to substrate orientations shown in the legend in panel (a).
Article metrics loading...