| AVS 55th International Symposium & Exhibition | |
| Magnetic Interfaces and Nanostructures | Wednesday Sessions |
| Session MI+NC-WeM |
| Session: | Magnetic Thin Films, Nanoparticles and Nanostructures |
| Presenter: | Z. Lu, University of Alabama |
| Authors: | Z. Lu, University of Alabama M.J. Walock, University of Alabama P. LeClair, University of Alabama W.H. Bulter, University of Alabama G.J. Mankey, University of Alabama |
| Correspondent: | Click to Email |
L10 FePt is a good candidate for ultrahigh density magnetic recording media because it exhibits a perpendicular anisotropy which has a very high value of Ku=7x107 erg/cm3. The high anisotropy allows for a smaller thermally stable magnetic volume in the written bits. However, writing the magnetic information on a film with such a high anisotropy is a technical challenge. To solve this problem, some new multilayered media such as exchange spring, exchanged composite and anisotropy graded media have been proposed. An important technical challenge for enabling these concepts is developing an ability to control the magnetic anisotropy of each magnetic layer. For FePt films, there are two methods to control the magnetic anisotropy, either by controlling the chemical order parameter S or by varying the composition to produce Fe-rich alloys. We will report our results obtained from epitaxial films fabricated by magnetron sputtering on MgO(100) substrates with Cr and Pt as buffer layers. By varying the growth temperature, epitaxial films of Fe50Pt50 were prepared with order parameters ranging from 0 to 0.95 as determined by x-ray diffraction. By carefully controlling the flux of the magnetron sources, epitaxial films of Fe100-xPtx with 25