Increase of ferromagnetic ordering temperature by the minority-band double-exchange interaction in SrRu{sub 1-x}Cr{sub x}O{sub 3}

Journal Article · Mon Aug 01 00:00:00 EDT 2005 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PhysRevB.72.054428· OSTI ID:20719296

Dabrowski, B; Kolesnik, S; Chmaissem, O; Maxwell, T; Avdeev, M; Barnes, P W; Jorgensen, J D ^[1]

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1. Physics Department, Northern Illinois University, DeKalb, Illinois 60115 (United States)

Structural, magnetic, and resistive properties of the chromium substituted SrRu{sub 1-x}Cr{sub x}O{sub 3} perovskites with increased ferromagnetic transition temperature from 163 to 188 K were studied for polycrystalline samples synthesized in air and at high pressure. The Cr solubility limit found at x=0.15 in air is controlled by geometrical constraints of the tolerance factor and can be extended to higher values through high-pressure synthesis at 3 GPa. A linear decrease of the lattice parameters and bond lengths and an increase of the bond angles with x are consistent with the substitution of smaller Cr{sup 4+/3+} for Ru{sup 4+/5+}. Similar decreases of the magnetic susceptibility {chi}{sub m} in the paramagnetic region above T{sub c} and the high-field magnetization at 5 K with increasing x also indicate the presence of the Cr{sup 4+/3+} and Ru{sup 4+/5+} ions. This chemical substitution creates a possible Ru{sup 4+/5+}(d{sup 4/3})-O{sup 2-}Cr{sup 4+/3+}(d{sup 2/3}) minority band double-exchange interaction which involves the Cr{sup 3+} and Cr{sup 4+} in magnetic ordering that enhances the ordering temperature. A reduced coercive field determined from the magnetization curves and a minimum of the resistivity point to decreased disorder for slightly substituted compositions x{approx}0.025.

• OSTI ID: 20719296
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 72, Issue 5; Other Information: DOI: 10.1103/PhysRevB.72.054428; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AIR
BOND ANGLE
BOND LENGTHS
CHROMIUM IONS
CHROMIUM OXIDES
COERCIVE FORCE
CRYSTAL STRUCTURE
ELECTRIC CONDUCTIVITY
ELECTRONS
EXCHANGE INTERACTIONS
FERROMAGNETIC MATERIALS
LATTICE PARAMETERS
MAGNETIC SUSCEPTIBILITY
MAGNETIZATION
OXYGEN IONS
PARAMAGNETISM
PEROVSKITES
POLYCRYSTALS
PRESSURE DEPENDENCE
PRESSURE RANGE GIGA PA
RUBIDIUM COMPOUNDS
RUTHENIUM IONS
SOLUBILITY
STRONTIUM COMPOUNDS
SYNTHESIS
TRANSITION TEMPERATURE