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We report on the magnetization at the Cr/MgO interface, which we studied through two complementary techniques: angle-resolved photoemission spectroscopy and polarized neutron reflectivity. We experimentally observe an enhanced interface magnetization at the interface, yet with values much smaller than the ones reported so far by theoretical and experimental studies on Cr(001) surfaces. Our findings cast some doubts on the interpretations on previous works and could be useful in antiferromagnetic spin torque studies. [ABSTRACT FROM AUTHOR]

We report on the correlations between magnetic anisotropy and strain state in CoFe2O4 ultrathin films grown on MgAl2O4(100) and MgAl2O4(111) substrates. By local strain analysis using the geometric phase method, a significant in-plane compressive strain is observed for the (001) orientation while a full relaxation is detected for the (111) orientation. The relaxation process in CoFe2O4(111) layers induces interface dislocations and a large amount of antiphase boundaries while a pseudomorphic growth is observed for the (001) direction, decreasing significantly the density of antiphase boundaries. By comparing the magnetoelastic energy terms, the correlation between strain state and resultant magnetization is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Lorentz transmission electron microscopy (LTEM) combined with in-situ magnetizing experiments is a powerful tool for the investigation of the magnetization of the reversal process at the micron scale. We have implemented this tool on a conventional transmission electron microscope (TEM) to study the exchange anisotropy of a polycrystalline Co35Fe65/NiMn bilayer. Semi-quantitative maps of the magnetic induction were obtained at different field values by the differential phase contrast (DPC) technique adapted for a TEM (SIDPC). The hysteresis loop of the bilayer has been calculated from the relative intensity of magnetic maps. The curve shows the appearance of an exchange-bias field reveals with two distinct reversal modes of the magnetization: the first path corresponds to a reversal by wall propagation when the applied field is parallel to the anisotropy direction whereas the second is a reversal by coherent rotation of magnetic moments when the field is applied antiparallel to unidirectional anisotropy direction. [Copyright &y& Elsevier]

Abstract: A generalized procedure for the in situ application of magnetic fields by means of the excitation of the objective lens for magnetic imaging experiments in Lorentz microscopy and electron holography is quantitatively described. A protocol for applying magnetic fields with arbitrary in-plane magnitude and orientation is presented, and a freeware script for Digital Micrograph™ is provided to assist the operation of the microscope. Moreover, a method to accurately reconstruct hysteresis loops is detailed. We show that the out-of-plane component of the magnetic field cannot be always neglected when performing quantitative measurements of the local magnetization. Several examples are shown to demonstrate the accuracy and functionality of the methods. [Copyright &y& Elsevier]