A study of uranium-based multilayers: II. Magnetic properties
| Autor: | Fabrice Wilhelm, G. H. Lander, Ross S Springell, Simon Brown, Laurence Bouchenoire, S. W. Zochowski, R. C. C. Ward, Sean Langridge, M. R. Wells, W. G. Stirling |
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| Rok vydání: | 2016 |
| Předmět: |
Condensed Matter - Materials Science
Materials science Magnetic moment Condensed matter physics Magnetometer Materials Science (cond-mat.mtrl-sci) FOS: Physical sciences Condensed Matter Physics law.invention Magnetic field SQUID Condensed Matter - Other Condensed Matter Magnetization law Curie temperature General Materials Science Neutron Anisotropy Other Condensed Matter (cond-mat.other) |
| Popis: | SQUID magnetometry and polarised neutron reflectivity measurements have been employed to characterise the magnetic properties of U/Fe, U/Co and U/Gd multilayers. The field dependence of the magnetisation was measured at 10K in magnetic fields from -70kOe to 70kOe. A temperature dependent study of the magnetisation evolution was undertaken for a selection of U/Gd samples. PNR was carried out in a field of 4.4kOe for U/Fe and U/Co samples (at room temperature) and for U/Gd samples (at 10K). Magnetic 'dead' layers of about 15 Angstrom were observed for U/Fe and U/Co samples, consistent with a picture of interdiffused interfaces. A large reduction in the magnetic moment, constant over a wide range of Gd layer thicknesses, was found for the U/Gd system (about 4 Bohr magnetons compared with 7.63 for the bulk metal). This could be understood on the basis of a pinning of Gd moments arising from a column-like growth mechanism of the Gd layers. A study of the effective anisotropy suggests that perpendicular magnetic anisotropy could occur in multilayers consisting of thick U and thin Gd layers. A reduction in the Curie temperature was observed as a function of Gd layer thickness, consistent with a finite-size scaling behaviour. 18 pages, 8 figures, submitted to J. Phys.: Condens. Matter |
| Databáze: | OpenAIRE |
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