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The fabrication of well‐defined, atomically sharp substrate surfaces over a wide range of lattice parameters is reported, which is crucial for atomically regulated epitaxial growth of complex oxide heterostructures. By applying a framework for controlled selective wet etching of complex oxides on the stable rare‐earth scandates (REScO3), apseudocubic = 0.394 – 0.404 nm, the large chemical sensitivity of REScO3 to basic solutions is exploited, which results in reproducible, single‐terminated surfaces. Time‐of‐flight mass‐spectroscopy measurements show that after wet etching the surfaces are predominantly ScO2 ‐terminated. Moreover, the morphology study of SrRuO3 thin‐film growth gives no evidence for mixed termination. Therefore, it is concluded that the REScO3 surfaces are completely ScO2 ‐terminated.

Results of experiments to study the effect of grain size and grain-size distribution on the intrinsic coercivity and the hysteresis loop of sintered Fe-Nd-B magnets are presented. It is shown that the intrinsic coercivity decreases as the average grain size of the magnet is increased. It is also shown that the intrinsic coercivity decreases linearly with the logarithm of the square of the grain size. This is consistent with the predictions made based upon the statistical model developed in Part I. An increase in the sintering temperature leads to an increase in the average grain size, which consequently leads to a narrower hysteresis loop and lower intrinsic coercivity compared to magnets sintered at a lower temperature. It is also shown that a heterogeneous grain-size distribution, such as a bimodal distribution, causes kinks to appear in the second quadrant of the hysteresis loop. By examining magnets with different fractions of large grains, the prediction that the magnitude of the kinks increases with the volume fraction of the large grains, has been verified experimentally.

We report the observation of ferromagnetic resonance (FMR) in SrRuO3 using the time-resolved magneto-optical Kerr effect. The FMR oscillations in the time-domain appear in response to a sudden, optically induced change in the direction of easy-axis anisotropy. The high FMR frequency, 250 GHz, and large Gilbert damping parameter, alpha approximately 1, are consistent with strong spin-orbit coupling. We find that the parameters associated with the magnetization dynamics, including alpha, have a nonmonotonic temperature dependence, suggestive of a link to the anomalous Hall effect.