  We report a giant magnetic moment enhancement of ferromagnetic nickel
nanoparticles (11 nm) embedded in multi-walled carbon nanotubes. High-energy
synchrotron x-ray diffraction experiment and chemical analysis are used to
accurately determine the ferromagnetic nickel concentration. Magnetic
measurements up to 900 K show an intriguing result-the saturation magnetization
of the nickel nanoparticles embedded in the multi-walled carbon nanotubes is
about 3.4 times as much as the value expected from the measured nickel
concentration while the Curie temperature is the same as that of bulk nickel.
The implication of this giant magnetic moment enhancement, whatever its origin,
is likely to be far reaching-it opens a new avenue for implementing
spin-electronics at the molecular level.
