The optical, electrical, and magnetic properties of magnetic Nd15Fe77B
8 and nonmagnetic Nd5Fe62B33 films have been investigated. It has been
found that within the visible (wavelengths 4400-6400 angstrom) the fi
lms are transparent with thickness less than 800 angstrom for magnetic
films and 1500 angstrom for nonmagnetic films. This is due to the dif
ference of the magnetic permeability mu between films. The oscillatory
behavior with thickness of the films is observed in the film samples.
The anomalous behaviors near the Curie temperature for both bulk- and
film-type samples are similar to that of the type-III ferrfomagnets.
The temperature at which the electrical resistance of the film-type sa
mples increases abruptly varies from 620 K for 1000 angstrom to 650 K
for 2000 angstrom.