| Autor: |
Ch. Muller, H. Mühlbauer, Günter Dumpich |
| Rok vydání: |
1999 |
| Předmět: |
|
| Zdroj: |
Journal of Magnetism and Magnetic Materials. 192:423-430 |
| ISSN: |
0304-8853 |
| DOI: |
10.1016/s0304-8853(98)01034-8 |
| Popis: |
Polycrystalline (Fe/Pd) n multilayers are grown onto sapphire substrates at room temperature in a UHV system. The number of periods n =40 and the thickness of Pd layers of t Pd =4 nm are kept constant, whereas the thickness of the Fe layers is varied from 1.5 to 5 nm. Structural properties are studied by in situ reflection high energy diffraction (RHEED), scanning tunnelling microscopy (STM) and ex situ by X-ray diffraction at small angles and large angles. Analyzing the experimental data using the program SUPREX we obtain interplanar distances of d Fe =2.03±0.01 A for an Fe layer thickness larger than about 2.5 nm as expected for (1 1 0) planes of BCC Fe. For Fe layers with thicknesses less than about 2.5 nm the interplanar distance is d Fe =2.1±0.01 A, which is close to the distance between (1 1 1) planes of FCC Fe with a lattice parameter of a =3.64 A. Magnetic susceptibility measurements at temperatures between 1.5 and 300 K for (Fe/Pd) n multilayers with FCC Fe yield a magnetic moment per Fe atom of μ =2.7±0.1 μ B , which is about 20% larger compared to μ =2.2 μ B for BCC Fe. We show that the occurrence of the large magnetic moment originates from FCC Fe being in the high spin (HS) state rather than from polarization effects of Pd at Fe/Pd interfaces. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect