Direct real space observation of magneto-electronic inhomogeneity in ultra-thin film La{sub 0.5}Sr{sub 0.5}CoO{sub 3−δ} on SrTiO{sub 3}(001)

Journal Article · Mon Sep 15 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4896283· OSTI ID:22303529

Kelly, S.; Galli, F.; Bose, Shameek; Sharma, M.

Recent magnetotransport and neutron scattering measurements implicate interfacial magneto-electronic phase separation as the origin of the degradation in transport and magnetism in ultra-thin film La{sub 1−x}Sr{sub x}CoO{sub 3} on SrTiO{sub 3}(001). Here, using low temperature scanning tunneling microscopy and spectroscopy the first direct, real space observation of this nanoscopic electronic inhomogeneity is provided. Films of thickness 12.4 nm (32 unit cells) are found to exhibit spatially uniform conductance, in stark contrast to 4.7 nm (12 unit cell) films that display rich variations in conductance, and thus local density of states. The electronic heterogeneity occurs across a hierarchy of length scales (5–50 nm), with complex correlations with both topography and applied magnetic fields. These results thus provide a direct observation of magneto-electronic inhomogeneity in SrTiO{sub 3}(001)/La{sub 0.5}Sr{sub 0.5}CoO{sub 3} at thicknesses below 6–7 nm, in good agreement with less direct techniques.

• OSTI ID: 22303529
• Journal Information: Applied Physics Letters, Vol. 105, Issue 11; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COBALT COMPOUNDS
CORRELATIONS
DENSITY
LANTHANUM COMPOUNDS
MAGNETIC FIELDS
MAGNETISM
MAGNETORESISTANCE
NEUTRON DIFFRACTION
OXYGEN COMPOUNDS
SCANNING TUNNELING MICROSCOPY
SPECTROSCOPY
STRONTIUM COMPOUNDS
STRONTIUM TITANATES
THICKNESS
THIN FILMS
TOPOGRAPHY