Phase separation in inhomogeneous mixed-valence systems: Application to manganites

Journal Article · Mon May 01 00:00:00 EDT 2000 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.373235· OSTI ID:20216218

Schlottmann, P ^[1]

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1. Department of Physics, Florida State University, Tallahassee, Florida 32306 (United States)

Manganites are inhomogeneous mixed-valence systems in which the Mn ions coexist in two magnetic configurations, Mn{sup 4+} and Mn{sup 3+}. We consider a simple alloy-analogy model with a charge interaction between nearest neighbor Mn ions. In addition there is an antiferromagnetic (AF) (superexchange) interaction between nearest neighbor ions of equal valence, while ions of different valence are coupled ferromagnetically (FM) (double exchange). Assuming classical spins, we show that the system is unstable to phase separation, i.e., to the coexistence of AF and charge ordered FM domains. In a magnetic field the FM domains increase at the expense of the AF ones. (c) 2000 American Institute of Physics.

• OSTI ID: 20216218
• Journal Information: Journal of Applied Physics, Vol. 87, Issue 9; Other Information: PBD: 1 May 2000; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
LANTHANUM OXIDES
CALCIUM OXIDES
MANGANESE OXIDES
PHASE STABILITY
ANTIFERROMAGNETIC MATERIALS
EXCHANGE INTERACTIONS
DOMAIN STRUCTURE
THEORETICAL DATA