Document Europhys. Lett., 67 (2) , pp. 287-293 (2004)
DOI: 10.1209/epl/i2004-10050-8
Electronic inhomogeneity at magnetic domain walls in strongly correlated systems
M. S. Rzchowski and R. JoyntPhysics Department, University of Wisconsin-Madison Madison, WI 53706, USA
(Received 16 January 2004; accepted in final form 3 May 2004)
Abstract
We show that nano-scale variations of the order parameter in
strongly correlated systems can induce local spatial regions such
as domain walls that exhibit electronic properties representative
of a different, but nearby, part of the phase diagram. This is
done by means of a Landau-Ginzburg analysis of a metallic
ferromagnetic system near an antiferromagnetic phase boundary.
The strong spin gradients at a wall between domains of different
spin orientation drive the formation of a new type of domain
wall, where the central core is an insulating antiferromagnet,
and connects two metallic ferromagnetic domains. We calculate the
charge transport properties of this wall, and find that its
resistance is large enough to account for recent experimental
results in colossal magnetoresistance materials. The
technological implications of this finding for switchable
magnetic media are discussed.
75.47.-m - Magnetotransport phenomena; materials for magnetotransport.
72.25.Mk - Spin transport through interfaces.
75.60.Ch - Domain walls and domain structure.
© EDP Sciences 2004