ABSTRACT
Homogeneity/inhomogeneity has stirred up interest as one of the
origins of unusual physical properties, say, a colossal magnetore-
sistive effect and superconductivity [1]. Taking advantage of first-
order transitions may give rise to either a homologous change of
volume or a phase separation (segregation). There are two scenarios
for understanding the appearance of unusual physical phenomena.
One scenario is that a homogeneous phase is formed perfectly in
the material. The other scenario is the phase separation among
multiphases, which has been claimed to be attributable to the
formation of the ordered state.We should not overlook that this type
of separation is essentially different from that well observed for the
binary-alloy system in the way of intrinsic, or perhaps it would be
more concrete to say that the former phase separation could occur
even in the perfect crystal due to the strong correlation between
electrons [3].
