Local lattice distortions and thermal transport in perovskite manganites

Journal Article · Wed Oct 01 00:00:00 EDT 1997 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.56.R8495· OSTI ID:632652

Cohn, J L ^[1]; Neumeier, J J ^[2]; Popoviciu, C P ^[1]; McClellan, K J ^[3]; Leventouri, T ^[2]

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1. Department of Physics, University of Miami, Coral Gables, Florida 33124 (United States)
2. Department of Physics, Florida Atlantic University, Boca Raton, Florida 33431 (United States)
3. Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

Measurements of thermal conductivity versus temperature and magnetic field are reported for perovskite manganites that exhibit ferromagnetic (FM), charge-ordering (CO), antiferromagnetic, and/or structural phase transitions. The data reveal a dominant lattice contribution to the heat conductivity with {kappa}{approximately}1{minus}2 W/mK near room temperature. The rather low values, implying a phonon mean free path on the order of a lattice spacing, are shown to correlate with static local distortions of the MnO{sub 6} octahedra. Modifications of the local structure are responsible for abrupt anomalies in the zero-field {kappa} at the FM, CO, and structural transitions, and for colossal magnetothermal resistance near the FM transition. {copyright} {ital 1997} {ital The American Physical Society}

• OSTI ID: 632652
• Journal Information: Physical Review, B: Condensed Matter, Vol. 56, Issue 14; Other Information: PBD: Oct 1997
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
PRASEODYMIUM OXIDES
THERMAL CONDUCTIVITY
MAGNETORESISTANCE
PHASE TRANSFORMATIONS
STRONTIUM OXIDES
MANGANESE OXIDES
LANTHANUM OXIDES
CALCIUM OXIDES
PEROVSKITES
FERROMAGNETIC MATERIALS
ANTIFERROMAGNETIC MATERIALS
CRYSTAL STRUCTURE
MELTING
MAGNETIZATION
ELECTRIC CONDUCTIVITY
SQUID DEVICES
ORDER-DISORDER TRANSFORMATIONS
ELECTRON-PHONON COUPLING