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J O Cross

Publications and source records attributed to J O Cross.

5 recordsLinked to original sources

Growth induced magnetic and chemical anisotropy in CoPt3 alloy films.

We report the results of polarized Co EXAFS experiments on a series of CoPt3 films grown by molecular beam epitaxy on (100) MgO singe crystal substrates over a range of temperatures from 473 K to 1073 K. These samples exhibit substantial perpendicular magnetic anisotropy that is strongly dependent on the substrate growth temperature Tg. We measure a preference for in-plane Co-Co pairs that is correlated with the magnetic properties.

Journal Article↗

Sample-angle feedback for diffraction anomalous fine-structure spectroscopy.

Diffraction anomalous fine-structure (DAFS) experiments measure Bragg peak intensities as continuous functions of photon energy near a core-level excitation. Measuring the integrated intensity at each energy makes the experiments prohibitively slow; however, in many cases DAFS can be collected quickly by measuring only the peak intensity at the center of the rocking curve. A piezoelectric-actuator-driven stage has been designed and tested as part of a sample-angle feedback circuit for locking onto the maximum of the rocking curve while the energy is scanned. Although software peak-tracking requires only a simple calculation of diffractometer angles, it is found that the additional hardware feedback dramatically improves the reproducibility of the data.

Journal Article↗