  We describe a strategy for using resonant soft x-ray scattering (RSXS) to
study the electronic structure of transition metal oxide quantum wires. Using
electron beam lithography and ion milling, we have produced periodic, patterned
arrays of colossal magnetoresistance (CMR) phase La(1-x)Sr(x)MnO(3) consisting
of ~ 5000 wires, each of which is 80 nm in width. The scattered intensity
exhibits a series of peaks that can be interpreted as Bragg reflections from
the periodic structure or, equivalently, diffraction orders from the
grating-like structure. RSXS measurements at the Mn L(2,3) edge, which has a
large magnetic cross section, show clear evidence for a magnetic superstructure
with a commensurate period of five wires, which we interpret as commensurately
modulated antiferromagnetism. This superstructure, which is accompanied by
non-trivial reorganization of the magnetization within each wire, likely
results from classical dipole interactions among the wires. We introduce a
simple, exactly soluble, analytic model of the scattering that captures,
semi-quantitatively, the primary features in the RSXS data; this model will act
as a foundation for forthcoming, detailed studies of the magnetic structure in
these systems.
