  In a material, the existence and coexistence of phases with very different
magnetic and electronic properties is both unusual and surprising. Manganites
in particular capture the imagination because they demonstrate a complexity
that belies their chemically single-phase nature. This complexity arises
because the magnetic, electronic and crystal structures interact with one
another to deliver exotic magnetic and electronic phases that coexist. This
coexistence is self-organized and yet readily susceptible to external
perturbations, permitting subtle and imaginative experiments of the type that
we describe here. Moreover, these experiments reveal that each competing phase
itself remains an incompletely solved mystery.
