In-plane anisotropy in the magnetic and transport properties of manganite ultrathin films

Journal Article · Sun Oct 01 00:00:00 EDT 2006 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.74.134419· OSTI ID:20853743

Orgiani, P; Polichetti, M; Zola, D ^[1]; Petrov, A Yu; Adamo, C; Aruta, C; Barone, C; De Luca, G M; Galdi, A; Maritato, L ^[2]

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1. CNR-INFM SuperMat and Department of Physics, University of Salerno, Via S. Allende, I - 84081 Baronissi (Saudi Arabia) (Italy)
2. CNR-INFM Coherentia and Department of Physics, University of Salerno, Via S. Allende, I - 84081 Baronissi (Saudi Arabia) (Italy)

To analyze the conducting and magnetic properties near the film and substrate interface in manganites, ultrathin films (thickness{<=}100 A ) of La{sub 0.7}Sr{sub 0.3}MnO{sub 3} were epitaxially grown by molecular-beam epitaxy on single-crystal (001) LaAlO{sub 3} (110) NdGaO{sub 3}, and (001) SrTiO{sub 3} substrates. Structural, magnetic, and magnetoresistive properties were investigated. All samples exhibit a substrate-independent decrease of the c-lattice parameter for thinnest films. Highly anisotropic behavior in both transport and magnetic properties were measured along the in-plane directions parallel to the substrate crystallographic axes. In particular, for the thinnest films (60 A ), the negative magnetoresistance at about 120 K with the average current along one of the crystallographic directions, is larger than the room-temperature colossal value. In the same low-temperature range, with the current along the other in-plane crystallographic direction, the magnetoresistance changes sign (resulting to be magnetic field independent for T{approx}150 K). Such an in-plane anisotropy of transport and magnetic properties is investigated with respect to possible intrinsic and extrinsic physical mechanisms.

• OSTI ID: 20853743
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 74, Issue 13; Other Information: DOI: 10.1103/PhysRevB.74.134419; (c) 2006 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
ALUMINATES
ANISOTROPY
ELECTRIC CURRENTS
INTERFACES
LANTHANUM COMPOUNDS
LATTICE PARAMETERS
LAYERS
MAGNETIC FIELDS
MAGNETIC PROPERTIES
MAGNETORESISTANCE
MANGANATES
MOLECULAR BEAM EPITAXY
MONOCRYSTALS
STRONTIUM TITANATES
SUBSTRATES
THIN FILMS