Chemistry Reference
In-Depth Information
(a)
(a)
(b)
(b)
0
5
10
15
20
-15 -10
-5
0
5
10
15
Velocity (mm/s)
Hyperfine field (T)
Fig. 5.12
119
Sn Mössbauer spectra and distribution of hyperfine field for (a) bulk Co
2
MnSn
Heusler alloy prepared by arc-melting, and (b)aCo
2
MnSn (40.2 nm) film prepared by atomically
controlled alternate deposition
5.7 Remarks
Magnetic hyperfine fields observed by Mössbauer spectroscopy are useful infor-
mation to characterize condensed matters. If a sample includes a certain amount of
Fe or Sn, Mössbauer measurements are easily applied. If the sample is able to be
enriched with Mössbauer isotope
57
Fe or
119
Sn, the limit of concentration required
for the measurements can be greatly reduced. Specific samples for interface studies
are prepared by doping with isotope selectively at the interface sites. In this article,
several
examples
of
Mössbauer
studies
using
interface-selectively
enriched
samples are introduced.
''Spintronics'' is a rapidly growing field where various novel phenomena are
being explored [
23
]. An important concept for spintronics is spin current and spin
polarization of conduction electrons is attracting a great attention. Concerning spin
polarization of conduction electrons, transferred from a ferromagnetic metal to
non-magnetic substance, interface magnetic properties of the ferromagnetic metal
may have a significant influence. Thus, the understanding of interface magnetism
seems to be crucial for spintronics researches. Application of Mössbauer spec-
troscopy will be useful for the study of such interface issues.
References
1. P. Gütlich, E. Bill, and A. X. Trautwein (eds.) Mössbauer Spectroscopy and Transition Metal
Chemistry (Springer, Berlin, 2011). Synchrotron Radiation Experiments have been surveyed
in Chap. 9
2. T. Shinjo, T. Takada (eds.) Metallic Superlattices (Elsevier, Amsterdam, 1987)
3. T. Shinjo, Surf. Sci. Repts. 12, 49 (1991)
4. S. Maekawa, T. Shinjo, Spin Dependent Transport in Magnetic Nanostructures (Taylor &
Francis, London, 2002)
